Compound Danshen Dripping Pill inhibits hypercholesterolemia/atherosclerosis-induced heart failure in ApoE and LDLR dual deficient mice via multiple mechanisms

Heart failure is the leading cause of death worldwide. Compound Danshen Dripping Pill (CDDP) or CDDP combined with simvastatin has been widely used to treat patients with myocardial infarction and other cardiovascular diseases in China. However, the effect of CDDP on hypercholesterolemia/atherosclerosis-induced heart failure is unknown. We constructed a new model of heart failure induced by hypercholesterolemia/atherosclerosis in apolipoprotein E (ApoE) and LDL receptor (LDLR) dual deficient (ApoE-/-LDLR-/-) mice and investigated the effect of CDDP or CDDP plus a low dose of simvastatin on the heart failure. CDDP or CDDP plus a low dose of simvastatin inhibited heart injury by multiple actions including anti-myocardial dysfunction and anti-fibrosis. Mechanistically, both Wnt and lysine-specific demethylase 4A (KDM4A) pathways were significantly activated in mice with heart injury. Conversely, CDDP or CDDP plus a low dose of simvastatin inhibited Wnt pathway by markedly up-regulating expression of Wnt inhibitors. While the anti-inflammation and anti-oxidative stress by CDDP were achieved by inhibiting KDM4A expression and activity. In addition, CDDP attenuated simvastatin-induced myolysis in skeletal muscle. Taken together, our study suggests that CDDP or CDDP plus a low dose of simvastatin can be an effective therapy to reduce hypercholesterolemia/atherosclerosis-induced heart failure.

The role of purslane in modulating diverse effects of high fat diet on biochemical, histological, and molecular parameters of rats' liver / O papel da beldroega na modulação de diversos efeitos da dieta rica em gordura nos parâmetros bioquímicos, histológicos e moleculares do fígado de ratos

Consuming a high-fat diet causes a harmful accumulation of fat in the liver, which may not reverse even after switching to a healthier diet. Different reports dealt with the role of purslane as an extract against high-fat diet; meanwhile, it was necessary to study the potential role of fresh purslane as a hypolipidemic agent. This study is supposed to investigate further the potential mechanism in the hypolipidemic effect of fresh purslane, by measuring cholesterol 7a-hydroxylase (CYP7A1) and low-density lipoprotein receptor (Ldlr). Rats were divided into two main groups: the first one is the normal control group (n=7 rats) and the second group (n=28 rats) received a high fat diet for 28 weeks to induce obesity. Then the high fat diet group was divided into equal four subgroups. As, the positive control group still fed on a high fat diet only. Meanwhile, the other three groups were received high-fat diet supplemented with a different percent of fresh purslane (25, 50 and 75%) respectively. At the end of the experiment, rats were sacrificed and samples were collected for molecular, biochemical, and histological studies. Current study reported that, supplementation of fresh purslane especially at a concentration of 75% play an important role against harmful effects of high-fat diet at both cellular and organ level, by increasing CYP7A1 as well as Ldlr mRNA expression. Also, there were an improvement on the tested liver functions, thyroid hormones, and lipid profile. Fresh purslane plays the potential role as a hypolipidemic agent via modulation of both Ldlr and Cyp7A, which will point to use fresh purslane against harmful effects of obesity.

O consumo de uma dieta rica em gordura causa um acúmulo prejudicial de gordura no fígado, que pode não reverter mesmo após a mudança para uma dieta mais saudável. Diferentes relatórios trataram do papel da beldroega como um extrato contra uma dieta rica em gordura; entretanto, foi necessário estudar o papel potencial da beldroega fresca como agente hipolipemiante. Este estudo pretende investigar mais profundamente o mecanismo potencial no efeito hipolipidêmico da beldroega fresca, medindo o colesterol 7a-hidroxilase (CYP7A1) e o receptor de lipoproteína de baixa densidade (Ldlr). Os ratos foram divididos em dois grupos principais: o primeiro é o grupo controle normal (n = 7 ratos) e o segundo grupo (n = 28 ratos) recebeu dieta rica em gorduras por 28 semanas para induzir a obesidade. Em seguida, o grupo de dieta rica em gordura foi dividido em quatro subgrupos iguais. Como, o grupo de controle positivo ainda se alimentava apenas com dieta rica em gordura. Enquanto isso, os outros três grupos receberam dieta rica em gordura suplementada com diferentes porcentagens de beldroegas frescas (25%, 50% e 75%), respectivamente. Ao final do experimento, os ratos foram sacrificados e amostras coletadas para estudos moleculares, bioquímica e histológicos. O estudo atual relatou que a suplementação de beldroegas frescas, especialmente a uma concentração de 75%, desempenha papel importante contra os efeitos prejudiciais da dieta rica em gordura em nível celular e orgânico, aumentando a expressão de CYP7A1 e Ldlr mRNA. Além disso, houve melhora nas funções hepáticas testadas, nos hormônios tireoidianos e no perfil lipídico. Beldroegas frescas desempenham papel potencial como agente hipolipemiante por meio da modulação de Ldlr e Cyp7A, o que apontará para o uso de beldroegas frescas contra os efeitos nocivos da obesidade.

The role of purslane in modulating diverse effects of high fat diet on biochemical, histological, and molecular parameters of rats liver

Abstract Consuming a high-fat diet causes a harmful accumulation of fat in the liver, which may not reverse even after switching to a healthier diet. Different reports dealt with the role of purslane as an extract against high-fat diet; meanwhile, it was necessary to study the potential role of fresh purslane as a hypolipidemic agent. This study is supposed to investigate further the potential mechanism in the hypolipidemic effect of fresh purslane, by measuring cholesterol 7a-hydroxylase (CYP7A1) and low-density lipoprotein receptor (Ldlr). Rats were divided into two main groups: the first one is the normal control group (n=7 rats) and the second group (n=28 rats) received a high fat diet for 28 weeks to induce obesity. Then the high fat diet group was divided into equal four subgroups. As, the positive control group still fed on a high fat diet only. Meanwhile, the other three groups were received high-fat diet supplemented with a different percent of fresh purslane (25, 50 and 75%) respectively. At the end of the experiment, rats were sacrificed and samples were collected for molecular, biochemical, and histological studies. Current study reported that, supplementation of fresh purslane especially at a concentration of 75% play an important role against harmful effects of high-fat diet at both cellular and organ level, by increasing CYP7A1 as well as Ldlr mRNA expression. Also, there were an improvement on the tested liver functions, thyroid hormones, and lipid profile. Fresh purslane plays the potential role as a hypolipidemic agent via modulation of both Ldlr and Cyp7A, which will point to use fresh purslane against harmful effects of obesity.

Resumo O consumo de uma dieta rica em gordura causa um acúmulo prejudicial de gordura no fígado, que pode não reverter mesmo após a mudança para uma dieta mais saudável. Diferentes relatórios trataram do papel da beldroega como um extrato contra uma dieta rica em gordura; entretanto, foi necessário estudar o papel potencial da beldroega fresca como agente hipolipemiante. Este estudo pretende investigar mais profundamente o mecanismo potencial no efeito hipolipidêmico da beldroega fresca, medindo o colesterol 7a-hidroxilase (CYP7A1) e o receptor de lipoproteína de baixa densidade (Ldlr). Os ratos foram divididos em dois grupos principais: o primeiro é o grupo controle normal (n = 7 ratos) e o segundo grupo (n = 28 ratos) recebeu dieta rica em gorduras por 28 semanas para induzir a obesidade. Em seguida, o grupo de dieta rica em gordura foi dividido em quatro subgrupos iguais. Como, o grupo de controle positivo ainda se alimentava apenas com dieta rica em gordura. Enquanto isso, os outros três grupos receberam dieta rica em gordura suplementada com diferentes porcentagens de beldroegas frescas (25%, 50% e 75%), respectivamente. Ao final do experimento, os ratos foram sacrificados e amostras coletadas para estudos moleculares, bioquímica e histológicos. O estudo atual relatou que a suplementação de beldroegas frescas, especialmente a uma concentração de 75%, desempenha papel importante contra os efeitos prejudiciais da dieta rica em gordura em nível celular e orgânico, aumentando a expressão de CYP7A1 e Ldlr mRNA. Além disso, houve melhora nas funções hepáticas testadas, nos hormônios tireoidianos e no perfil lipídico. Beldroegas frescas desempenham papel potencial como agente hipolipemiante por meio da modulação de Ldlr e Cyp7A, o que apontará para o uso de beldroegas frescas contra os efeitos nocivos da obesidade.

The role of purslane in modulating diverse effects of high fat diet on biochemical, histological, and molecular parameters of rats' liver / O papel da beldroega na modulação de diversos efeitos da dieta rica em gordura nos parâmetros bioquímicos, histológicos e moleculares do fígado de ratos

Abstract Consuming a high-fat diet causes a harmful accumulation of fat in the liver, which may not reverse even after switching to a healthier diet. Different reports dealt with the role of purslane as an extract against high-fat diet; meanwhile, it was necessary to study the potential role of fresh purslane as a hypolipidemic agent. This study is supposed to investigate further the potential mechanism in the hypolipidemic effect of fresh purslane, by measuring cholesterol 7a-hydroxylase (CYP7A1) and low-density lipoprotein receptor (Ldlr). Rats were divided into two main groups: the first one is the normal control group (n=7 rats) and the second group (n=28 rats) received a high fat diet for 28 weeks to induce obesity. Then the high fat diet group was divided into equal four subgroups. As, the positive control group still fed on a high fat diet only. Meanwhile, the other three groups were received high-fat diet supplemented with a different percent of fresh purslane (25, 50 and 75%) respectively. At the end of the experiment, rats were sacrificed and samples were collected for molecular, biochemical, and histological studies. Current study reported that, supplementation of fresh purslane especially at a concentration of 75% play an important role against harmful effects of high-fat diet at both cellular and organ level, by increasing CYP7A1 as well as Ldlr mRNA expression. Also, there were an improvement on the tested liver functions, thyroid hormones, and lipid profile. Fresh purslane plays the potential role as a hypolipidemic agent via modulation of both Ldlr and Cyp7A, which will point to use fresh purslane against harmful effects of obesity.

Resumo O consumo de uma dieta rica em gordura causa um acúmulo prejudicial de gordura no fígado, que pode não reverter mesmo após a mudança para uma dieta mais saudável. Diferentes relatórios trataram do papel da beldroega como um extrato contra uma dieta rica em gordura; entretanto, foi necessário estudar o papel potencial da beldroega fresca como agente hipolipemiante. Este estudo pretende investigar mais profundamente o mecanismo potencial no efeito hipolipidêmico da beldroega fresca, medindo o colesterol 7a-hidroxilase (CYP7A1) e o receptor de lipoproteína de baixa densidade (Ldlr). Os ratos foram divididos em dois grupos principais: o primeiro é o grupo controle normal (n = 7 ratos) e o segundo grupo (n = 28 ratos) recebeu dieta rica em gorduras por 28 semanas para induzir a obesidade. Em seguida, o grupo de dieta rica em gordura foi dividido em quatro subgrupos iguais. Como, o grupo de controle positivo ainda se alimentava apenas com dieta rica em gordura. Enquanto isso, os outros três grupos receberam dieta rica em gordura suplementada com diferentes porcentagens de beldroegas frescas (25%, 50% e 75%), respectivamente. Ao final do experimento, os ratos foram sacrificados e amostras coletadas para estudos moleculares, bioquímica e histológicos. O estudo atual relatou que a suplementação de beldroegas frescas, especialmente a uma concentração de 75%, desempenha papel importante contra os efeitos prejudiciais da dieta rica em gordura em nível celular e orgânico, aumentando a expressão de CYP7A1 e Ldlr mRNA. Além disso, houve melhora nas funções hepáticas testadas, nos hormônios tireoidianos e no perfil lipídico. Beldroegas frescas desempenham papel potencial como agente hipolipemiante por meio da modulação de Ldlr e Cyp7A, o que apontará para o uso de beldroegas frescas contra os efeitos nocivos da obesidade.

Bioinformatics Analysis of LDLR Gene Mutation that Shed a New Light on Red Yeast Rice Monacolin K Treatment � Systematic Review

Background: Hypercholesteremia is the major cause of cardiovascular diseases. It results from elevated cholesterol levels in the blood. LDL cholesterol is removed from the circulation by using the LDL receptor. Red mold rice or red yeast rice is produced by fermentation of the Monascus Purpureus yeast on rice. Many researchers suggest that the active component in Red Yeast Rice (monacolin k) serves as a treatment for hypercholesteremic patients. Methods: By using NCBI databases, specifically GenBank to analyze DNA sequence and mRNA sequence of LDLR gene. GenBank file format was helpful to extract an accession number of the gene, number of amino acids, exons, and length of nucleotides. FASTA format was also useful to retrieve the nucleotide sequence and get the function of the protein. BLAST was used to compare the protein product of the LDLR gene between humans and pan paniscus (pygmy chimpanzee). Results: In accession number NC_000019, the number of amino acids in protein product is 44389 bp, and the number of exons found is 18. On the other hand, the gene is located in chromosome 19. The function of LDLR gene is to control the production of LDL receptor where the low-density lipoprotein particles attach to it and are taken into the cell ending up in the lysosome where the protein is degraded and cholesterol is made which will inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase that controls the production of cholesterol. Finally, many organisms have the same gene like dogs, cows, mice, rats, zebrafish, and frogs. Conclusion: Mutation in the LDLR gene causing high level of cholesterol in the blood especially LDL (Low-density Lipoprotein). Monacolin k that found in red yeast rice (RYR) is safe and natural alternative treatment for hypercholesteremic patients by lowering the cholesterol level in the blood.

Effect of Shuangyu Tiaozhi Decoction on HNF1α/PCSK9/LDLR Signaling Pathway in Liver of Hypercholesterolemic Rats / 中国实验方剂学杂志

Objective:To observe the expression of hepatocyte nuclear factor 1<italic>α</italic> （HNF1<italic>α</italic>）， proprotein convertase subtilisin/kexin type 9 （PCSK9） and low-density lipoprotein cholesterol （LDLR） in hypercholesterolemia rat liver， and investigate the mechanism of Shuangyu Tiaozhi Decoction regulating cholesterol metabolism and attenuating hypercholesterolemia. Method:After providing a high-fat diet for 4 weeks， 40 SD rats were selected， 8 of which were randomly selected as normal group and fed a normal diet， and the remaining 32 rats were fed a high-fat diet. The rats successfully established as hypercholesterolemic model， were randomized into 4 groups： model group， low dose of Shuangyu Tiaozhi decoction group （7.8 g·kg^-1）， high dose of Shuangyu Tiaozhi decoction group （15.6 g·kg^-1）， and simvastatin group （4 mg·kg^-1）， with 8 rats in each group. The drugs were continuously given for 8 weeks. Serum total cholesterol （TC）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C）， high-density lipoprotein cholesterol （HDL-C） were measured. The pathomorphological changes in liver were observed by hematoxylin and eosin （HE） staining. The immunohistochemistry was used to detect PCSK9 and LDLR expression in liver. The mRNA and protein expression levels of HNF1<italic>α</italic>， PCSK9 and LDLR were determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. Result:Compared with normal group， the TC， TG， LDL-C levels in model group were significantly increased （<italic>P</italic><0.01）， the morphology showed obvious liver steatosis. The mRNA and protein expression of HNF1<italic>α</italic> and PCSK9 were increased （<italic>P</italic><0.05）， the mRNA and protein expression of LDLR was decreased （<italic>P</italic><0.05）. Compared with model group， the serum TC， TG， LDL-C levels were significantly lowered in the Shuangyu Tiaozhi decoction high-dose group （<italic>P</italic><0.01）， the serum TC， LDL-C levels were significantly lowered in the Shuangyu Tiaozhi decoction low-dose group and simvastatin group （<italic>P</italic><0.05，<italic>P</italic><0.01）， while no significant effect was observed on the serum HDL-C levels in each treatment group. The liver steatosis decreased in each treatment group. The mRNA and protein expression of HNF1<italic>α</italic> was obviously decreased in each treatment group （<italic>P</italic><0.05，<italic>P</italic><0.01）， the mRNA and protein expression of PCSK9 was obviously decreased in Shuangyu Tiaozhi decoction low and high-dose groups （<italic>P</italic><0.05，<italic>P</italic><0.01）， the mRNA expression of PCSK9 was significantly increased in the simvastatin group （<italic>P</italic><0.01）， while the protein expression showed a downward trend. The LDLR mRNA levels were significantly increased in each treatment group （<italic>P</italic><0.01）， the LDLR protein expression was significantly increased in Shuangyu Tiaozhi high-dose group （<italic>P</italic><0.01）， and showed an upward trend in Shuangyu Tiaozhi low-dose group and simvastatin group. Results of immunohistochemistry showed PCSK9 expression was weakly positive， the expression of LDLR was strongly positive in each treatment group. The therapeutic effect of Shuangyu Tiaozhi decoction high-dose group was more remarkable than simvastatin group， while there was no obvious difference between the Shuangyu Tiaozhi decoction low-dose group and simvastatin group. Conclusion:Shuangyu Tiaozhi decoction may reduce the blood lipid levels through HNF1<italic>α</italic>/PCSK9/LDLR signaling pathway， play an active role on regulating cholesterol metabolism and alleviating high-fat diet-induced hypercholesterolemia.

Potentiating CD8

Metabolic regulation has been proven to play a critical role in T cell antitumor immunity. However, cholesterol metabolism as a key component of this regulation remains largely unexplored. Herein, we found that the low-density lipoprotein receptor (LDLR), which has been previously identified as a transporter for cholesterol, plays a pivotal role in regulating CD8

A successful pregnancy outcome of homozygous familial hypercholesterolaemia patient on statin therapy

@#Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disorder of lipoprotein metabolism mainly due to mutation of the low-density lipoprotein (LDL)-receptor gene (LDLR). It is a life-threatening disease that causes accelerated, multi-vessel atherosclerosis presented in early childhood. Pregnancy in HoFH may pose early coronary morbidity and mortality to both the foetus and mother. The combination of HoFH and pregnancy can be a fatal condition. While statins are very effective in lowering low-density lipoprotein cholesterol (LDL-C) levels, they are generally contraindicated during pregnancy, thus their use during pregnancy is uncommon. On the other hand, lipid apheresis (LA) has turned into an effective treatment to control cholesterol level amid pregnancy. However, the procedure is not widely available in our region. To date, there are scarcely documented case reports of HoFH in pregnancy in which the majority of them underwent LA to keep LDL-C at a low level. We report a rare case of successful pregnancy outcome of HoFH patient treated with lipid-lowering drugs including statin without LA therapy. Apart from that, we also discussed the genetic findings of the proband and all screened family members in which to the best of our knowledge, the first study using the whole-exome sequencing technique to identify the causative gene mutations for familial hypercholesterolaemia among the Malaysian population.

Effect of Evodia on Lipid Metabolism in Hyperlipidemia Mice / 中国实验方剂学杂志

Objective::To study the effect of evodia on lipid metabolism and low-density lipoprotein-receptor(LDL-R) mRNA expression in hyperlipidemia mice. Method::Kunming mice (n=80) were randomly divided into normal control group (n=20) and model group (n=60). Serum lipids of the model group were measured after 3 weeks.After successful modeling, the mice can be randomly divided into 5 groups (with 10 in each group): model group (equivalent normal saline), positive control group (simvastatin, 5 mg·kg-1·d-1), drug group (evodia of 5.25, 10.5, 21 mg·kg- 1·d- 1). The mice were given drugs for 3 weeks.Htoxylin-eosin(HE) staining was used to observe the liver cell structure and the change of aortic arch atherosclerosis in the mice.The enzyme linked immunosorbent assay kit was used to test the contents of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total serum adiponectin (ADPN) in serum of the mice.The expression of LDL-R mRNA in liver of each group was detected by reverse transcription-polymerase chain reaction (RT-PCR). Result::Liver HE staining showed hepatocyte swelling with steatosis in the model group, and alleviated liver steatosis in high-dose, medium-dose evodia and simvastatin groups.HE staining showed damages on the aortict arch wall in the model group, with obvious intima thickening and inflammatory cell infiltration.The intima was thickened obviously in the low-dose group, and the structure of aortic vessel wall was clear in the high-dose group.Compared with the normal group, TC, TG and HDL-C levels in serum of the model group were increased, while HDL-C level was decreased (P<0.01). Serum TC and TG levels of mice in the medium and high-dose groups decreased, whereas LDL-C and HDLl-C levels increased in low, medium and high-dose groups (P<0.05, P<0.01). Compared with the normal group, the adiponectin level in the model group was decreased, while the serum adiponectin levels in medium and high-dose groups were significantly increased (P<0.01). The LDL-R mRNA expression in the liver of mice in the model group was significantly reduced compared with the normal group (P<0.01). The LDL-R mRNA expression in medium and high-dose evodia groups was significantly increased compared with the model group (P<0.01). Conclusion::Evodia can improve the tendency of hepatic lesions and aortic atherosclerosis in hyperlipidemia mice, which may be related to the regulation of adiponectin level, the reduction of lipid content in mice and the up-regulation of LDL-R mRNA expression in mice liver.

Caracterização funcional in vitro de variantes no gene PCSK9 identificadas em pacientes com Hipercolesterolemia Familial / In vitro functional characterization of PCSK9 variants identified in patients with Familial Hypercholesterolemia

A Hipercolesterolemia Familial (HF) é uma doença genética do metabolismo das lipoproteínas, caracterizada pelo aumento do colesterol plasmático, transportado principalmente pela lipoproteína de baixa densidade (LDL). A HF é causada principalmente por mutações nos genes LDLR, APOB e PCSK9. As mutações conhecidas na PCSK9 podem levar ao aumento ou diminuição da função proteolítica da proteína, as quais são associadas ao aumento ou diminuição da LDL-c plasmática, respectivamente. Com o projeto genoma humano surgiram novos métodos de sequenciamento, o que resultou em um grande número de novas variantes genéticas relacionadas à HF. Entretanto, os mecanismos pelos quais essas variantes influenciam na concentração do colesterol e sua interferência na resposta terapêutica não estão totalmente elucidados. O objetivo do presente trabalho foi avaliar in vitro o efeito de variantes na região codificadora e reguladora do gene PCSK9 identificadas em pacientes HF utilizando sequenciamento de nova geração. Para a caracterização funcional das variantes na região codificadora da PCSK9, primeiramente foi avaliado o impacto dessas variantes na interação PCSK9-LDLR via Docking molecular. Células HEK293FT foram transfectadas com as diferentes construções da PCSK9, e posteriormente, foram utilizadas em ensaios para avaliar a atividade do LDLR e a internalização de LDL por citometria de fluxo. Para as variantes na região reguladora da PCSK9, foi realizado uma predição in silico do possível efeito de variantes na região 3UTR na ligação de miRNAs. A avalição da interação entre os miRNAs preditos, e a região 3UTR da PCSK9, e o possível impacto nessa interação na presença de variantes na região 3UTR, foi realizada em células HEK293FT transfectadas com um plasmídeo contendo a 3UTR da PCSK9 e um gene repórter da Gaussia luciferase, juntamente com um plasmídeo de expressão contendo os miRNAs de interesse. Foi também estudado o efeito dos miRNAs preditos sobre a expressão, RNAm e proteína, da PCSK9 via RT-qPCR e Western blot, em células HepG2. Foram identificadas 9 variantes na região codificadora da PCSK9, e duas, E32K e R469W, foram selecionadas para os ensaios posteriores. Para a R469W foi observada uma possível alteração conformacional a qual poderia aumentar a afinidade da PCSK9 pelo LDLR. Para a E32K, uma possível associação com HF foi observada em uma família brasileira com ascendência japonesa. As variantes E32K e R469W apresentaram uma redução na atividade do LDLR de 5 e 11%, respectivamente em comparação a PCSK9-WT. Entretanto, não foram observadas reduções estaticamente significativas na atividade do LDLR e na internalização da LDL em células transfectadas com ambas as variantes. Dez variantes foram encontradas na região 3UTR da PCSK9, entre elas três foram selecionadas por impactar a ligação de quatro miRNAs. Nossos dados demonstraram uma redução significativa na expressão da PCSK9 em células HepG2 transfectadas com os miR-4721 e miR-564 (p=0,036 e p=0,010, respectivamente). Porém, não foi observada diferenças na expressão da luciferase em células transfectadas com esses miRNAs, não sendo possível validar a interação miRNA-RNAm. As variantes no gene PCSK9 identificadas no nosso estudo podem não explicar individualmente o fenótipo HF, mas podem contribuir para a severidade da doença juntamente com outras variantes em outros genes

Familial Hypercholesterolemia (FH) is a genetic disorder of lipoprotein metabolism, characterized by elevated plasma cholesterol levels, mostly carried by low-density lipoprotein (LDL). FH is mainly caused by mutations in three genes, LDLR, APOB, and PCSK9. Gain-of-function mutations in PCSK9 reduce LDL receptor levels, resulting in high levels of LDL cholesterol in the plasma. Loss-of-function mutations lead to higher levels of the LDL receptor, resulting in lower LDL cholesterol levels. The Human Genome Project led to a faster technological development related to sequencing methods, which allowed identifying many novel variants associated with FH. However, the mechanisms by which these variants influence cholesterol levels and their interference in therapeutic response are not fully understood. The aim of the present study was to perform an in vitro characterization of the effect of PCSK9 variants identified in FH patients using Next-Generation Sequencing. For the functional characterization of variants in the coding region of PCSK9, the impact of these variants on PCSK9-LDLR interaction was evaluated by molecular docking. HEK293FT cells were transiently transfected with different PCSK9 constructs, and the amount of cell surface LDLR and LDL internalization were determined by flow cytometry. For the variants in PCSK9 3UTR region, an in silico prediction of PCSK9 3UTR variants in miRNA seed regions and target sites was performed. To determine whether the predicted miRNAs directly interact with PCSK9 3UTR region, HEK293FT cells were co-transfected with a vector containing a PCSK9 3'UTR region and a Gaussia luciferase reporter gene, together with an expression plasmid containing the miRNAs of interest. The effect of the predicted miRNAs on the expression of PCSK9 was evaluated using RT-qPCR and Western blot in HepG2 cells transiently transfected with miRNA mimics. Nine missense variants were identified in PCSK9 gene. E32K e R469W were chosen for further analysis. For R469W, a possible conformational change was observed that could increase the affinity of PCSK9 for LDLR, when compared to the wild-type. For E32K, a possible association with FH in a Brazilian family with Japanese ancestry was observed. E32K and R469W had a 5% and 11% decreased level of cell surface LDLR, respectively, as compared with WT-PCSK9. However, no significant reduction in the number of cell surface LDLR and LDL internalization was observed in transfected cells for both variants. Ten variants were found in PCSK9 3'UTR region, of which three were selected for affecting the binding of four miRNAs. Our data demonstrated a significant downregulation of PCSK9 in cells transfected with miR-4721 and miR-564 miRNA mimics, compared to cells transfected with a scramble control (p=0,036 and p=0,010, respectively). However, no differences in luciferase expression were observed in cells transfected with these miRNAs, therefore, it was not possible to experimentally validate miRNA-mRNA interaction. PCSK9 variants found in our study may not fully explain FH phenotype but may contribute to the severity of the disease together with other variants in other genes

Ultrassequenciamento exômico dos principais genes relacionados com a hipercolesterolemia familial / Ultrasequensing exomic of the main genes related to familial hypercholesterolemia

A frequência de Hipercolesterolemia Familial (HF) ainda é desconhecida no Brasil, principalmente pela ausência de estudos com caracterização genotípica associada à fenotípica. Os dados epidemiológicos existentes se baseiam apenas no fenótipos e carecem do diagnóstico molecular confirmatório. O objetivo do presente estudo foi identificar as principais causas genéticas da HF em pacientes diagnosticados fenotipicamente através de um painel exômico com 61 genes a fim de contribuir para um sistema de confirmação do diagnostico molecular em uma amostra da população brasileira. Para isso foram incluídos 141 pacientes, não aparentados, portadores de HF atendidos pelo setor de dislipidemias do Instituto Dante Pazzanese de Cardiologia, Laboratório de Analises Clinicas da Faculdade de Ciências Farmacêuticas da Universidade Federal do Rio Grande do Norte e do Programa Hipercol Brasil do Instituto do Coração. As amostras de sangue periférico foram obtidas para determinações fenotípicas laboratoriais e extração de DNA genômico. A biblioteca de DNA foi construída utilizando o kit Nextera® Rapid Capture Enrichment Custom enriquecendo os éxons de 61 genes que direta ou indiretamente estão relacionados com metabolismo do colesterol. O ultrassequenciamento foi realizado utilizando kit MiSeq Reagent (300 a 500 ciclos) na plataforma MiSeq (Illumina). Os resultados de sequenciamento foram inicialmente alinhados a uma sequência referência e analisados para eliminação de falsos positivos, segundo os parâmetros de qualidade, tais como: cobertura mínima de 30x, frequência do alelo alterado maior que 20% e diferença da distribuição das leituras entre as sequências nucleotídicas menor que 15%. Foram identificadas 472 diferentes variantes em 56 dos genes presentes no painel, sendo 45 consideradas como não descritas. Nos genes APOA1, APOA2, LIPC, RBP4 e TIMP1 não foram observadas variantes dentro dos critérios estabelecidos. Das variantes observadas 25 identificadas em 30 (21,2%) pacientes já tinha sido publicadas em relação à HF nos três principais genes (LDLR, APOB e PCSK9), confirmando o diagnóstico. Foi caracterizado genotipicamente outras dislipidemias primárias em 7 pacientes, sem diagnóstico molecular de HF, através de variantes identificadas no ultrassequenciamento em outros genes. Dos 104 pacientes que não possuíam nenhuma variante já previamente caracterizada, 69 possuíam variantes relacionados com o metabolismo do colesterol. As variantes sem patogenicidade conhecida foram avaliadas através de ferramentas de predição in silico e 22 delas possuíam características sugestivas de patogenicidade em pelo menos 4 das ferramentas utilizadas, duas delas também mostraram alterar a estrutura da proteína segundo análises de docking molecular. Foram identificadas também 223 variantes em região não transcritas (UTR). Quando realizada as análises estatística de todas as variantes identificadas, observamos associação de 13 variantes com concentrações mais elevadas de colesterol da LDL, 5 com concentrações mais elevadas de apolipoproteina B-100, 5 com concentrações mais elevadas de colesterol total, 6 com presença de arco córneo, 2 com manifestação de xantelasmas, 2 com ausência de xantomas e 3 com a presença de doença arterial coronariana. Dessas 6 variantes já haviam sido previamente descritas com HF ou algum outro fenótipo associado e 2 não tinham citação na literatura pesquisada, mas possuíam característica patogênica para a proteína segundo as ferramentas de predição in silico. Este estudo permitiu a identificação das causas genéticas da HF em pacientes brasileiros diagnosticados fenotipicamente, mostrando que a técnica escolhida permitiu caracterizar 21,2% dos pacientes. Além disso, foi possível identificar outras dislipidemias primárias e caracterizar algumas variantes que, apesar de necessitarem serem validadas, indicam uma possível associação com a HF, aumentando o esclarecimento do fenótipo com o genótipo para 74,5%. Este estudo também possibilitou a identificação de novas variantes que devem ser avaliadas para confirmar associação com a doença e utilizar para o diagnóstico propondo um novo painel poligênico

The frequency of Familial Hypercholesterolemia (FH) is still unknown in Brazil, mainly due to the absence of studies with genotypic characterization associated with phenotype. Existing epidemiological data are based only on the phenotypes and lack the confirmatory molecular diagnosis. The aim of the present study was to identify main genetic causes of FH in patients diagnosed phenotypically through an exomic panel with 61 genes in order to contribute to a system of confirmation molecular diagnosis in a sample of the Brazilian population. To this end, 141 non-related patients with FH treated by the dyslipidemia sector of the Institute Dante Pazzanese of Cardiology, Clinical Analysis Laboratory of the Faculty of Pharmaceutical Sciences of the University Federal of Rio Grande do Norte and the Hipercol Brazil Program of the Heart Institute. Peripheral blood samples were obtained for laboratory phenotypic determinations and extraction of genomic DNA. The DNA library was constructed using the Nextera® Rapid Capture Enrichment Custom kit, enriching with éxons of 61 genes that are directly or indirectly related to cholesterol metabolism. Ultrasequencing was performed using MiSeq Reagent kit (300 to 500 cycles) on the MiSeq platform (Illumina). The sequencing results were initially aligned to a reference sequence and analyzed for false positive elimination according to quality parameters such as: minimum coverage of 30x, altered allele frequency greater than 20%, and difference in the distribution of reads between sequences nucleotides less than 15%. 472 different variants were identified in 56 of the genes present in the panel, of which 45 were considered not described. In the APOA1, APOA2, LIPC, RBP4 and TIMP1 genes no variants were observed within the established criteria. In 25 of the variants observed presents in 30 (21.2%) patients had already been published in relation to FH in the three main genes (LDLR, APOB and PCSK9), confirming the diagnosis. Other primary dyslipidemias were caracterized genotypically in 7 patients, without molecular diagnosis of HF, through variants identified in ultrasequencing in other genes. Of the 104 patients who did not have any previously characterized variant, 69 had variants related to cholesterol metabolism. The variants without known pathogenicity were evaluated using in silico prediction tools and 22 of them had characteristics suggestive of pathogenicity at least 4 of the tools used, two of them also showed to alter the structure of the protein according to molecular docking analyzes. Were also identified 223 non-transcribed region (UTR) variants. Statistical analysis of all the variants identified showed association of 13 variants with higher concentrations of LDL cholesterol, 5 with higher concentrations of apolipoprotein B-100, 5 with higher concentrations of total cholesterol, 6 with presence of an arc corneal, 2 with manifestation of xanthelasms, 2 with absence of xanthomas and 3 with the presence of coronary artery disease. Of these 6 variants had previously been described with HF or some other associated phenotype and 2 had no citation in the researched literature, but had a pathogenic characteristic for the protein according to in silico prediction tools. This study allowed the identification of the genetic causes of FH in Brazilian patients diagnosed phenotypically, showing that the technique chosen allowed to characterize 21.2% of the patients. In addition, it was possible to identify other primary dyslipidemias and to characterize some variants that, although they need to be validated, indicate a possible association with HF, increasing the clarification of the phenotype with the genotype to 74.5%. This study also allowed the identification of new variants that should be evaluated to confirm association with the disease and to use for the diagnosis proposing a new polygenic panel

Estudos da atividade do receptor da LDL em pacientes com Hipercolesterolemia Familial / Studies of LDL receptor activity in patients with familial hypercholesterolemia

A hipercolesterolemia familial (HF) é uma doença autossômica dominante considerada como uma das formas mais graves de hiperlipidemia, assim como, a principal causa de morbi-mortalidade por ser o principal fator desencadeante da aterosclerose. A alteração primária e mais freqüente da HF incide no gene do receptor da LDL (LDLr), sabe-se que mais de 1600 mutações são descritas na literatura e a principal consequência dessas alterações resultam no comprometimento da remoção da LDL, aumentando a concentração plasmática. Atualmente, o ultrasequenciamento genômico permite gerar muitos dados, que podem identificar novas mutações gênicas de forma eficiente, reprodutiva e rápida. No entanto, somente a validação da nova mutação por atividade funcional pode realmente estabelecer a associação com a doença. O presente estudo tem como objetivo realizar a análise da atividade do receptor da LDL, identificadas através do sequenciamento de alto rendimento, no gene LDLr realizado pelo nosso grupo de pesquisa e correlacionar com dados clínicos, in vitro, in silico e estrutural. Para cumprir esta meta, os linfócitos T dos portadores de HF foram isolados do sangue periférico, cultivados e submetidos a estímulo para a expressão de receptores da LDL, incubados com LDL marcada para avaliação de ligação e interiorização pelas células de cada paciente. Dos 30 pacientes selecionados para esse estudo, 63% apresentaram mutação no LDLR, sendo que quase todas as variantes (p.Gly373Asp, p.Asp601His, p.Ile488Thr, p.Gly549Asp, p.Gly592Glu e Gly681Asp) são localizadas no segundo domínio entre os éxons 7 ao 14. De acordo com o docking molecular a variante p.Gly592Glu (rs137929307), que já foi identificada na população polonesa, espanhola e brasileira, já relacionada com a HF, pode aumentar a interação do LDLr com a ApoB e consequentemente o modo de interação entre as proteínas, no estudo in vitro foi possível notar um aumento tanto na média de fluorescência da ligação e da ligação e interiorização em relação a quantidade de LDLr na superfície celular

Familial hypercholesterolemia (HF) is an autosomal dominant disease considered as one of the most severe forms of hyperlipidemia, as well as the main cause of morbidity and mortality because it is the main triggering factor for atherosclerosis. The primary and more frequent alteration of the HF affects the LDL receptor gene (LDLr), it is known that more than 1600 mutations are described in the literature and the main consequence of these alterations results in the compromise of the LDL removal, increasing the plasma concentration. Nowadays, genomic ultrasequencing allows the generation of many data, which can identify new gene mutations efficiently, reproductively and rapidly. However, only the validation of the new functional activity mutation can actually establish association with the disease. The aim of the present study was to analyze LDL receptor activity, identified by high-throughput sequencing, in the LDLr gene performed by our research group and to correlate with clinical, in vitro, in silico and structural data. To meet this goal, the T lymphocytes from the HF carriers were isolated from the peripheral blood, cultured and challenged for the expression of LDL receptors, incubated with labeled LDL for binding assessment and internalization by the cells of each patient. Of the 30 patients selected for this study, 63% had a mutation in LDLR, and almost all variants (p.Gly373Asp, p.Asp601His, p.Ile488Thr, p.Gly549Asp, p.Gly592Glu and Gly681Asp) are located in the second domain between exons 7 to 14. According to the molecular docking the variant p.Gly592Glu (rs137929307), which has already been identified in the Polish, Spanish and Brazilian population, already related to HF, can increase the interaction of LDLr with ApoB and consequently the mode of interaction between proteins, in the in vitro study it was possible to note an increase in both the mean fluorescence of binding and binding and internalization in relation to the amount of LDLr on the cell surface

Familial Hypercholesterolemia / Монголын Анагаах Ухаан

@#Familial hypercholesterolemia (FH) (OMIM#143890) is the most common metabolic autosomal disorder. The prevalence of the homozygous FH has been reported as 1 in a million in the general population, compared to much more mild form heterozygous FH with prevalence of 1 in 200-500. Mutations in the low-density lipoprotein receptor (LDLR), apolipoprotein B (ApoB), proprotein convertase subtilin/kexin9 (PCSK9), and low-density lipoprotein receptor adapter protein 1 (LDLRAP1) genes have been linked to FH. These mutations result in a disorder in low-density lipoprotein cholesterol (LDL-C) catabolism, and significantly increasing the levels of LDL-C, total cholesterol in serum, leading to specific clinical signs such as tendon xanthoma, corneal arcus, cardiovascular diseases, and early death from coronary heart disease if left unattended. Therefore, there is an ardent need for early diagnosis followed by aggressive therapeutic intervention and lifestyle modification. Currently, FH can be diagnosed either clinically or genetically. There have three main clinical diagnostic criteria for FH: the US MedPed Program, the Simon Broom Register Group in the UK, and the Netherland’s criteria. The occurrence of so many different LDLR mutations and their widespread distribution throughout the gene imposes severe practical limitations on simple genetic screening. Indeed, exon by exon sequencing of LDLR and other genes in each patient is the best screening genetic methods of choice. Although the hypercholesterolemia associated with FH can be controlled with cholesterol-lowering drug therapy (statins and other), patient response can vary quite widely.

Effects of squalene on expression of LDLR in HepG2 cells and its mechanism / 中国药理学通报

Aim To investigate the effect of squalene on LDLR expression in HepG2 cells and its mechanism of down-regulated cholesterol. Methods The prolifer-ation of HepG2 cells exposed to squalene at different concentrations was measured by MTT assay. The effect of squalene on the expression of LDLR in HepG2 cells was measured by flow cytometry and fluorescence mi-croscopy. The effect of different concentrations of squa-lene on the interaction between SCAP and Insig2, two key protein molecules of SREBP pathway, was assayed by FRET technology. Results MTT results showed that squalene had inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner. Flow cy-tometry and fluorescence microscopy results showed that squalene enhanced LDLR expression in HepG2 cells compared with the control group. The results of FRET technology revealed that compared with model control group, the YFP fluorescence value in Squalene group dramatically declined, and the YFP fluorescence value of each drug group decreased with the range of 5~25 μmol·L-1 squalene concentration. Conclusions Squalene may promote the expression of LDLR in HepG2 cells through inhibiting the interaction between SCAP and Insig2 proteins in SREBP pathway, which may confirm that squalene is a potential novel drug for the down-regulation of cholesterol level.

Niacin accelerates LDL-C uptake in HepG2 cells via downregulation of PCSK9 / 中国药理学通报

Aim To explore the effects of niacin on LDL-C uptake and metabolism in HepG2 cells,and to clarify the functions of niacin in lipid-lowering and slo-wing the atherosclerosis process,thus to provide a sci-entific basis for niacin as a lipid-lowering drug in clini-cal development.Methods Oil red O staining was used to observe HepG2 cells after lipid uptake.Enzy-matic method was used to determine the content of in-tracellular free cholesterol (FC)and total cholesterol (TC).The LDLR levels on the surface of cell mem-brane were detected by immunofluorescence flow cy-tometer.The mRNA and protein expressions of LDLR, SREBP2 and PCSK9 were analyzed by qPCR and Western blot.Results The results of oil red O staining showed that the rate of oil red O-positive cells and the number of red lipid droplets were significantly in-creased in niacin group than control group.Niacin sig-nificantly increased the levels of TC and FC in HepG2 cells(P <0.05 ).What’s more,niacin significantly upregulated the expression of LDLR and significantly downregulated the protein expression of PCSK9,while it had no effect on the expression of SREBP2.Conclu-sion Niacin accelerates LDL-C uptake probably via downregulating the expression of PCSK9 and reducing the degradation of LDLR protein in HepG2 cells.

Hypolipidemic effect of powder of Panax notoginseng and its mechanism / 中草药

Objective: To investigate the hypolipidemic effects of powder of Panax notoginseng (PPN) and explore its possible mechanism. Methods: Hyperlipidemic rats model was established, and orally given three dosages of PPN for 8 weeks. The levels of serum ALT, AST, TC, TG, and LDL-C were detected. The pathological changes of liver tissues were observed by H&E staining. Gene expressions of hepatic low density lipoprotein receptor (LDLR), SIRT1, and LXR-α were measured with RT-PCR analysis. Protein expression of SREBP-2 and SCAP was determined by Western blotting. Results: Three dosages of PPN significantly decreased serum ALT, AST, TC, TG, and LDL-C levels. Histological data indicated that PPN notably reduced liver injury and hepatic steatosis in hyperlipidemic rats. In molecular study, mRNA expression of hepatic LDLR and SIRT1 was up-regulated and LXR-α gene expression was down-regulated in PPN treated rats. Additionally, PPN significantly reduced protein expression of SREBP-2 and SCAP. Conclusion: The positive effect of PPN on hyperlipidemic rats may be related to the inhibition of cholesterol synthesis of PPN through the up-regulation of SIRT1 and down-regulation of LXR-α and SCAP/SREBP-2 signaling pathway. Additionally, PPN could up-regulate hepatic LDLR mRNA expression and improve uptake of LDL-C in circulation.

Down-regulation of single-stranded DNA-binding protein 1 expression induced by HCMV infection promotes lipid accumulation in cells

The objective of this study was to observe the infection of human cytomegalovirus (HCMV) to human umbilical vein endothelial cells, and its effect on the expression of single-stranded DNA-binding protein (SSBP1) and on lipid metabolism in endothelial cells. We screened the differential expression of mRNAs after HCMV infection by suppression subtractive hybridization and the expression levels of SSBP1 mRNA and protein after HCMV infection by real-time PCR and western blot. After verification of successful infection by indirect immunofluorescent staining and RT-PCR, we found a differential expression of lipid metabolism-related genes including LDLR, SCARB, CETP, HMGCR, ApoB and LPL induced by HCMV infection. The expression levels of SSBP1 mRNA and protein after HCMV infection were significantly down-regulated. Furthermore, we found that upregulation of SSBP1 inhibited the expression of atherosclerosis-associated LDLR, SCARB, HMGCR, CETP as well as the accumulation of lipids in the cells. The results showed that the inhibition of SSBP1 by HCMV infection promotes lipid accumulation in the cells.

Experiment of THP-1 macrophage foam-cell formation through mTOR signal pathway activation induced by inflammatory stress / 中国药理学通报

Aim To investigate if LPS increases the sterol regulatory element binding proteins ( SREBPs ) cleavage-activating protein ( SCAP )-SREBP2 expres-sion by activation of mTOR signal pathway in THP-1 macrophages , upgrading LDLr level , causing foam-cell formation .Methods THP-1 macrophages were incu-bated in serum free medium in the absence of 5 mg?L-1 LDL alone , or 5 mg? L-1 LDL plus 200 μg? L-1 LPS, or 5 mg? L-1 LDL plus 200 μg? L-1 LPS plus 10 μg? L-1 rapamycin .Morphological examination of macrophages was performed with Oil Red O staining . Expression changes of LDLr , SREBP2, SCAP, S6K1 and mTOR mRNA were detected by real time quantita-tive polymerase chain reaction ( PCR ) .Western blot was used to analyze protein expression changes of LD-Lr, S6K1 and mTOR.Translocation of SCAP-SREBP2 complex from the endoplasmic reticulum ( ER ) to the Golgi was determined by confocal microscopy .Results LPS enhanced transformation of THP-1 macrophages into foam cells by increased uptake of lipid as evi-denced by Oil Red O assay .LPS increased mRNA lev-els of LDLr, SREBP2, SCAP, S6K1 and mTOR ( P <0.05) .Rapamycin reduced the mRNA levels of LDLr , SREBP2,SCAP,S6K1 and mTOR induced by LPS ( P<0.05 ) .Western blot demonstrated that LPS also caused over-expression of protein of LDLr , S6K1 and mTOR(P<0.05).Rapamycin reduced the expression of protein of LDLr, S6K1 and mTOR induced by LPS ( P <0.05 ) .Confocal microscopy demonstrated LPS caused an escape of SCAP-SREBP2 complex from the ER to the Golgi .Rapamycin inhibited the translocation of SCAP-SREBP2 complex from the ER to the Golgi . Conclusions Inflammatory stress increases SCAP/SREBP2 expression by activation of mTOR signal path-way, resulting in an escape of SCAP-SREBP2 complex from the ER to the Golgi , furthermore elevating LDLr expression and causing foam-cell formation .Rapamy-cin reverses the activation of mTOR signal pathway and decreases lipid deposition in THP-1 macrophages in-duced by LPS .

Efeitos da administração de eritropoietina na dislipidemia e na hipertrofia ventricular esquerda de camundongos hiperlipidêmicos / Effects of administration of the erythropoietin in dyslipidemia and left ventricular hypertrophy of hyperlipidemic mice

O principal objetivo deste trabalho foi avaliar os efeitos da eritropoietina (EPO) no perfil lipídico e na hipertrofia ventricular esquerda (HVE) de camundongos LDLr-/- alimentados com dieta hiperlipídica, Foram utilizados vinte e quatro camundongos LDLr-/-, machos, 3 meses de idade, equinumericamente divididos em 3 grupos: Grupo S, alimentados com dieta padrão, Grupo HL, alimentados com dieta hiperlipídica (20% de gordura total e 1,25% de colesterol, 0,5 % ácido cólico), Grupo HL+EPO, alimentados com dieta hiperlipídica e tratados com EPO na dose semanal de 200UI/kg via subcutânea, Após 75 dias de experimento foram avaliadas a desenvoltura da HVE e as concentrações séricas de glicose, triglicérides (TG), colesterol total (CT) e de lipoproteínas de baixa densidade (LDL), de muita baixa densidade (VLDL), e de alta densidade (HDL) além da razão entre a massa ventricular esquerda e a massa total do animal: massa ventricular (mg)/massa do animal(g), O protocolo experimental foi aprovado pelo Comitê de Ética Experimental da Universidade sob o número 13A/2010, Ao final do período experimental, os camundongos do grupo HL apresentaram desenvolvimento de HVE com aumento nas concentrações séricas de CT, LDL, VLDL, TG e glicose e redução do HDL, quando comparados com parâmetros dos camundongos do grupo S, O uso da EPO pelo grupo HL+EPO aumentou significativamente (p<0,05) as concentrações séricas do HDL, quando comparados com o grupo HL, e preveniu a HVE, Além disso, reduziu as concentrações de CT, LDL e glicose (p<0,05), Entretanto, a EPO não foi eficiente em impedir a hipertrigliceridemia e tão pouco foi capaz de reduzir as concentrações de VLDL induzidas pela dieta HL, Em conclusão, a EPO apresentou alguns efeitos cardioprotetores, prevenindo a HVE bem como corrigindo algumas das variáveis bioquímicas induzidas pela dieta HL, Estes efeitos podem estar em parte, relacionados ao aumento das concentrações plasmáticas de HDL...

The main purpose of this work was to evaluate the effects of erythropoietin (EPO) on the lipid profile and in left ventricular hypertrophy (LVH) in mice LDLr-/-, fed a high fat diet. Were used twenty-four mice LDLr- / -, male, 3 months old, proportionally divided in 3 groups: S Group, fed with standard diet; HL Group, fed with high fat diet (20% fat total and 1.25% cholesterol, 0.5% cholic acid); HL + EPO Group, fed with high-fat diet and treated with EPO on weekly dose of 200UIkg, subcutaneously. After 75 days of experiment the development of LVH, serum concentrations of glucose, triglycerides (TG), total cholesterol (TC), and low, very low and high density lipoprotein (LDL, VLDL and HDL, respectively) in addition to the left ventricular mass ratio and the total mass of the animal (ventricular mass(mg)/total animal mass(g)) were evaluated. The experimental protocol was approved by the University Ethics Committee of the Experimental Studies under the number 13A/2010. At the end of the trial period, the mice of the HL presented development of LVH with increase in serum concentrations of CT, LDL, VLDL, TG and glucose and a decreased of HDL concentrations, when compared with parameters of mice of the Group S. The use of EPO by HL+EPO group increased serum concentrations of HDL, compared with the HL group (p<0,05) and prevented LVH. In addition, reduced the serum concentrations of TC, LDL, and glucose (p<0,05). However, EPO was not efficient in preventing the hypertriglyceridemia and still, wasn?t able to reduce VLDL concentrations induced by the diet HL. In conclusion, the EPO presented some cardio protective effects, preventing the HVE as well as correcting some of the biochemical variables diet HL-induced. These effects may be, in part, related to increased plasma concentrations of HDL...

Recombinant hepatitis C virus-envelope protein 2 interactions with low-density lipoprotein/CD81 receptors

Hepatitis C virus (HCV) envelope protein 2 (E2) is involved in viral binding to host cells. The aim of this work was to produce recombinant E2B and E2Y HCV proteins in Escherichia coli and Pichia pastoris, respectively, and to study their interactions with low-density lipoprotein receptor (LDLr) and CD81 in human umbilical vein endothelial cells (HUVEC) and the ECV304 bladder carcinoma cell line. To investigate the effects of human LDL and differences in protein structure (glycosylated or not) on binding efficiency, the recombinant proteins were either associated or not associated with lipoproteins before being assayed. The immunoreactivity of the recombinant proteins was analysed using pooled serum samples that were either positive or negative for hepatitis C. The cells were immunophenotyped by LDLr and CD81 using flow cytometry. Binding and binding inhibition assays were performed in the presence of LDL, foetal bovine serum (FCS) and specific antibodies. The results revealed that binding was reduced in the absence of FCS, but that the addition of human LDL rescued and increased binding capacity. In HUVEC cells, the use of antibodies to block LDLr led to a significant reduction in the binding of E2B and E2Y. CD81 antibodies did not affect E2B and E2Y binding. In ECV304 cells, blocking LDLr and CD81 produced similar effects, but they were not as marked as those that were observed in HUVEC cells. In conclusion, recombinant HCV E2 is dependent on LDL for its ability to bind to LDLr in HUVEC and ECV304 cells. These findings are relevant because E2 acts to anchor HCV to host cells; therefore, high blood levels of LDL could enhance viral infectivity in chronic hepatitis C patients.