Genetic analysis of a patient with familial hypercholesterolemia due to variant of LDLR gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze variant of LDLR gene in a patient with familial hypercholesterolemia (FH) in order to provide a basis for the clinical diagnosis and genetic counseling.@*METHODS@#A patient who had visited the Reproductive Medicine Center of the First Affiliated Hospital of Anhui Medical University in June 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was applied to the patient. Candidate variant was verified by Sanger sequencing. Conservation of the variant site was analyzed by searching the UCSC database.@*RESULTS@#The total cholesterol level of the patient was increased, especially low density lipoprotein cholesterol. A heterozygous c.2344A>T (p.Lys782*) variant was detected in the LDLR gene. Sanger sequencing confirmed that the variant was inherited from the father.@*CONCLUSION@#The heterozygous c.2344A>T (p.Lys782*) variant of the LDLR gene probably underlay the FH in this patient. Above finding has provided a basis for genetic counseling and prenatal diagnosis for this family.

Molecular mechanism of astragaloside Ⅳ against atherosclerosis by regulating miR-17-5p and PCSK9/VLDLR signal pathway / 中国中药杂志

This study explores the regulatory effect of astragaloside Ⅳ on miR-17-5 p and its downstream proprotein convertase subtillisin/kexin type 9(PCSK9)/very low density lipoprotein receptor(VLDLR) signal pathway, aiming at elucidating the mechanism of astragaloside Ⅳ against atherosclerosis(AS). In cell experiment, oxidized low-density lipoprotein(ox-LDL) was used for endothelial cell injury modeling with vascular smooth muscle cells(VSMCs). Then cells were classified into the model group, miR-17-5 p inhibitor group, blank serum group, and astragaloside Ⅳ-containing serum group based on the invention. Afterward, cell viability and the expression of miR-17-5 p, VLDLR, and PCSK9 mRNA and protein in cells in each group were detected. In animal experiment, 15 C57 BL/6 mice were used as the control group, and 45 ApoE~(-/-) mice were classified into the model group, miR-17-5 p inhibitor group, and astragaloside Ⅳ group, with 15 mice in each group. After 8 weeks of intervention, the peripheral serum levels of interleukin-6(IL-6), interleukin-10(IL-10), and tumor necrosis factor-α(TNF-α), and the expression of miR-17-5 p, VLDLR, and PCSK9 mRNA in the aorta of mice were detected. The pathological changes of mice in each group were observed. According to the cell experiment, VSMC viability in the miR-17-5 p inhibitor group and the astragaloside Ⅳ-containing serum group was higher than that in the model group(P<0.05). The mRNA and protein expression of miR-17-5 p and VLDLR in VSMCs in the miR-17-5 p inhibitor group and the astragaloside Ⅳ-containing serum group was lower than that in the model group(P<0.05), but the mRNA and protein expression of PCSK9 was higher than that in the model group(P<0.05). As for the animal experiment, the levels of IL-6 and TNF-α in the peripheral serum of the miR-17-5 p inhibitor group and the astragaloside Ⅳ group were lower(P<0.05) and the serum level of IL-10 was higher(P<0.05) than that of the model group. The mRNA expression of miR-17-5 p and VLDLR in the aorta in the miR-17-5 p inhibitor group and the astragaloside Ⅳ group was lower(P<0.05), and PCSK9 mRNA expression was higher(P<0.05) than that in the model group. Pathological observation showed mild AS in the miR-17-5 p inhibitor group and the astragaloside Ⅳ group. In summary, astragaloside Ⅳ can prevent the occurrence and development of AS. The mechanism is that it performs targeted regulation of miR-17-5 p, further affecting the PCSK9/VLDLR signal pathway, inhibiting vascular inflammation, and thus alleviating endothelial cell injury.

Expression and Significance of Low-Density Lipoprotein-Related Receptors 5 and 6 in the Wnt/β-Catenin Signaling Pathway in Childhood Acute Lymphoblastic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the significance of low-density lipoprotein receptor-related protein 5 and 6 (LRP5/6) in the Wnt/β-catenin signaling pathway in the pathogenesis and prognosis of childhood acute lymphoblastic leukemia (ALL).@*METHODS@#A total of 43 children who were newly diagnosed and achieved complete remission after remission induction therapy were enrolled. The children before treatment were included in incipient group, and after treatment when achieved complete remission included in remission group. A total of 39 children with immune thrombocytopenia were enrolled in control group. Three milliliter bone marrow samples were collected from above-mentioned each group. QRT-PCR was used to determine the mRNA expression of LRP5 and LRP6 in blood mononuclear cells of bone marrow. Western blot was used to detect the protein expression of LRP5 and LRP6. According to the protein expression levels of LRP5 and LRP6, the children were divided into low-expression group and high-expression group, and the clinical biological characteristics were compared between these two groups. Survival analysis was performed by Kaplan-Meier method.@*RESULTS@#Both mRNA and protein expression levels of LRP5 and 6 were upregulated in the incipient group compared with the control and remission group (P<0.05). The mRNA and protein expressions of LRP5 and LRP6 in the high-risk group were higher than those in the medium-risk group (P<0.05), it is the same as in the medium-risk group than the low-risk group (P<0.05). The mRNA and protein expressions of LRP5 and 6 positively correlated with risk degree in the incipient group (r@*CONCLUSION@#The high expression of LRP5/6 may be one of the pathogenesis of childhood ALL, and the degree of LRP5/6 increase may be related to the risk level.

Portador Heterozigoto Composto de Hipercolesterolemia Familiar Causada por Variantes no LDLR / Compound Heterozygous Familial Hypercholesterolemia Caused by LDLR Variants

Resumo A hipercolesterolemia familiar (HF) é uma doença genética causada por um defeito primário no gene que codifica o receptor da LDL. Mutações diferentes no mesmo gene caracterizam um heterozigoto composto, mas pouco se sabe sobre o fenótipo dos portadores. Portanto, neste estudo, descrevemos o rastreamento em cascata de uma família brasileira com essa característica. O caso-índice é um homem de 36 anos, com colesterol total (CT) de 360 mg/dL (9,3 mmol/L) e concentração de LDL-c de 259 mg/dL (6,7 mmol/L), além de xantomas de tendão de Aquiles, obesidade e pré-hipertensão. A genotipagem identificou as mutações 661G>A, 670G>A e 682G>A, no exon 4, e 919G>A, no exon 6. A mesma mutação no exon 4 foi observada no filho do caso-índice (7 anos), que também tem hipercolesterolemia e xantomas tendinosos, ao passo que a filha do caso-índice (9 anos) apresenta mutação no exon 6 e hiperlipidemia, sem xantomas. Em suma, este relato permite uma melhor compreensão acerca da base molecular da HF no Brasil, um país multirracial, onde é esperada uma população heterogênea.

Abstract Familial hypercholesterolemia (FH) is a genetic disease caused by a primary defect in the LDL-receptor gene. Distinct variants in the same gene characterize a compound heterozygote, but little is known about the phenotypes of the carriers. Therefore, herein, we describe the cascade screening of a Brazilian family with this characteristic. The index case, a 36-year-old male, had a total cholesterol level of 360 mg/dL (9.3 mmol/L) and LDL-c value of 259 mg/dL (6.7 mmol/L), in addition to Achilles tendon xanthomas, obesity and prehypertension. Genotyping identified the variants 661G>A, 670G>A, 682G>A in exon 4 and 919G>A in exon 6. The same variant in exon 4 was found in the index case's son (7-y), who also had hypercholesterolemia and xanthomas, while the index case's daughter (9-y) had the variant in exon 6 and hyperlipidemia, without xanthomas. In summary, this report allows for a better insight into the molecular basis of FH in Brazil, a multi-racial country where a heterogeneous population is expected.

Phenotype of definite familial hypercholesterolemia with negative genetic study in Argentina / Fenotipo de hipercolesterolemia familiar definitivo con estudio genético negativo en Argentina

Abstract Objective: Familial hypercholesterolemia (FH) is a monogenic disease, associated with variants in the LDLR, APOB and PCSK9 genes. The initial diagnosis is based on clinical criteria like the DLCN criteria. A score > 8 points qualifies the patient as "definite" for FH diagnosis. The detection of the presence of a variant in these genes allows carrying out familial cascade screening and better characterizes the patient in terms of prognosis and treatment. Methods: In the context of the FH detection program in Argentina (Da Vinci Study) 246 hypercholesterolemic patients were evaluated, 21 with DLCN score > 8 (definite diagnosis).These patients were studied with next generation sequencing to detect genetic variants, with an extended panel of 23 genes; also they were adding the large rearrangements analysis and a polygenic score of 10 SNP (single nucleotide polymorphism) related to the increase in LDL-c. Results: Of the 21 patients, 10 had variants in LDLR, 1 in APOB with APOE, 1 in LIPC plus elevated polygenic score, and 2 patients showed one deletion and one duplication in LDLR, the later with a variation in LIPA. It is highlighted that 6 of the 21 patients with a score > 8 did not show any genetic alteration. Conclusions: We can conclude that 28% of the patients with definite clinical diagnosis of FH did not show genetic alteration. The possible explanations for this result would be the presence of mutations in new genes, confusing effects of the environment over the genes, the gene-gene interactions, and finally the impossibility of detecting variants with the current available methods.

Resumen Objetivo: La hipercolesterolemia familiar (HF) es una enfermedad monogénica asociada a variantes en los genes RLDL, APOB y PCSK9. El diagnóstico inicial se basa en criterios clínicos, como el de la red de clínica de lípidos holandesa (DLCN). Un puntaje > 8 puntos califica al paciente como "definitivo" para diagnóstico de HF. La identificación de una variante en estos genes permite realizar el cribado en cascada familiar y caracterizar mejor al paciente en cuanto al pronóstico y el tratamiento. Métodos: En el marco del Programa de Detección de HF en Argentina (Estudio Da Vinci) se evaluó a 246 pacientes hipercolesterolémicos, 21 con puntaje DLCN > 8 (diagnóstico definitivo). Se estudió a estos pacientes con secuenciación de próxima generación para reconocer variantes genéticas, con un panel ampliado de 23 genes, sumado al análisis de grandes rearreglos y por último se aplicó un score poligénico de 10 SNP (polimorfismo de nucleótido único) relacionados con aumento del c-LDL. Resultados: De los 21 pacientes, 10 presentaron variantes en RLDL, uno en APOB junto a APOE, uno en LIPC más puntaje poligénico elevado, dos pacientes con una deleción y una duplicación en RLDL y este último caso con una variante en LIPA. Es destacable que 6 de los 21 pacientes con puntaje DLCN > 8 no mostraron ninguna alteración genética. Conclusiones: El 28% de los pacientes con diagnóstico clínico definitivo de HF no evidenció alteración genética. Las posibles explicaciones de este resultado serían la presencia de mutaciones en nuevos genes, los efectos confundidores del ambiente sobre los genes o la interacción gen-gen y por último la imposibilidad de detectar variantes con la metodología actual disponible.

Evaluation of Collagen Fibers, MMP2, MMP9, 8-OHdG and Apoptosis in the Aorta of Ovariectomized LDL Knockout Mice Submitted to Aerobic Exercise / Avaliação de Fibras de Colágeno, MMP2, MMP9, 8-OH-Dg e Apoptose na Aorta de Ratas LDL Nocaute Ovariectomizadas Submetidas a Exercício Aeróbico

Abstract Background: In menopause, there is greater cellular exposure to oxidative stress, related to the decreased antioxidative effects of estrogen. These metabolic changes favor the progression of cardiovascular diseases, such as atherosclerosis. Abnormal function of the aorta - the most important artery - is associated with many cardiovascular diseases. Collagen, especially types I and III, is one of the most important aortic wall components and it can be affected by many factors, including menopause. The 8-OHdG is one of the main markers of DNA oxidative damage induced by reactive oxygen species (ROS). Objective: We aimed to investigate effects of moderate aerobic training on the ascending aorta of LDL-knockout (LDL-KO) and ovariectomized female mice. Methods: A total of 15 C57BL/6 mice and 15 LDL-KO mice were divided into experimental groups. The thickness and volume density of types I and III collagen fibers were performed by morphoquantitative analysis, whereas the MMP-2 and MMP-9 and 8-OHdG were detected by immunohistochemistry and apoptosis was detected by the TUNEL assay. The significance level for all tests was p < 0.05. Results: Exercise causes an increase in the thickness of the aorta in LDL-KO groups, particularly accentuated in the ovariectomized groups. The type I collagen fibers showed an increase in volume density influenced by training in both Control groups and in the LDL-KO group. Type III collagen density decreased in both groups. The MMP-2 showed moderade immunostaining in the tunica media in LDL-KO groups, which did not occur in the control groups and the MMP-9 stained irregularly in all tissues. The marker 8-OhdG was stronger in the exercise training groups. Additionally, the ovariectomy, the exercise training and the LDL-KO treatments increased apoptosis. Conclusion: These results suggest that moderate-intensity aerobic exercise in ovariectomized mice associated to an increase in LDL rate possibly increases oxidative stress and apoptosis induction.

Resumo Fundamento: Na menopausa, há maior exposição celular ao estresse oxidativo, relacionada à diminuição dos efeitos antioxidantes do estrogênio. Essas alterações metabólicas favorecem a progressão das doenças cardiovasculares, como a aterosclerose. A função anormal da aorta - a artéria mais importante - está associada a muitas doenças cardiovasculares. O colágeno, especialmente os tipos I e III, é um dos mais importantes componentes da parede da aorta e pode ser afetado por muitos fatores, incluindo a menopausa. Por sua vez, 8-OHdG é um dos principais marcadores de danos oxidativos do DNA induzidos por espécies reativas de oxigênio (EROS). Objetivo: Investigar os efeitos do treinamento aeróbico moderado na aorta ascendente de camundongos fêmeas, nocaute para LDL (LDL-KO) e ovariectomizadas. Métodos: Um total de 15 animais C57BL/6 e 15 animais LDL-KO foram divididos em grupos experimentais. A espessura e a densidade de volume das fibras de colágeno tipos I e III foram realizadas por análise morfoquantitativa; MMP-2 e MMP-9 e 8-OHdG foram detectadas por imunohistoquímica; e a apoptose foi detectada pelo ensaio TUNEL. O nível de significância adotado para todos os testes realizados foi p < 0,05. Resultados: o exercício causa aumento da espessura da aorta em grupos LDL-KO, particularmente acentuada em grupos ovariectomizados. As fibras de colágeno de tipo I mostraram aumento da densidade de volume influenciado pelo treinamento em animais controle e LDL-KO. A densidade do colágeno tipo III diminuiu em ambos os grupos. A MMP-2 mostrou imunomarcação moderada na túnica média em animais LDL-KO; em grupos controle, a MMP-9 marcou irregularmente em todos os tecidos. O marcador 8-OHdG foi mais forte nos grupos de treinamento de exercícios. Além disso, a ovariectomia, o treinamento físico e os tratamentos de LDL-KO aumentaram a apoptose. Conclusão: Esses resultados sugerem que exercícios aeróbicos de intensidade moderada em camundongos ovariectomizados associados ao aumento da taxa de LDL, possivelmente, aumentam o estresse oxidativo e a indução da apoptose.

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

Nanotechnology for the treatment of deep endometriosis: uptake of lipid core nanoparticles by LDL receptors in endometriotic foci

OBJECTIVE: Rapidly dividing cells in multiple types of cancer and inflammatory diseases undergo high low density lipoprotein (LDL) uptake for membrane synthesis, and coupling an LDL-like nanoemulsion, containing lipid nanoparticles (LDE) to a chemotherapeutic agent efficiently targets these cells without significant systemic effects. This was a prospective exploratory study that evaluated the uptake of a radioactively labeled LDE emulsion by receptors of endometriotic foci and the capacity of the LDE for cellular internalization. METHODS: The lipid profile of each patient was determined before surgery, and labeled LDE were injected into fourteen patients with intestinal or nonintestinal endometriosis. The radioactivity of each tissue sample (intestinal endometriosis, nonintestinal endometriosis, healthy peritoneum, or topical endometrium) was measured. RESULTS: The group with intestinal endometriosis presented higher levels of plasma LDL but lower LDE uptake by foci than the nonintestinal group, suggesting less cell division and more fibrosis. The uptake of LDE was highest in the topical endometrium, followed by the healthy peritoneum, and lowest in the endometriotic lesion. Since the endometriotic foci showed significant LDE uptake, there was likely increased consumption of LDL by these cells, similar to cells in cancers and inflammatory diseases. Plasma cholesterol levels had no influence on LDE uptake, which showed that the direct delivery of the nanoemulsion to target tissues was independent of serum lipoproteins. There were no significant differences in the parameters (p>0.01) because of the small sample size, but the findings were similar to those of previous studies. CONCLUSION: Nanotechnology is a promising therapeutic option for surgery and hormonal blockage for deep endometriosis, with a lower complication rate and no systemic side effects.

Metabolites profiling and hypolipidemic/hypocholesterolemic effects of persimmon (Diosyros kaki Thumb.) by different processing procedures: in vitro and in vivo studies / 한국영양학회지

PURPOSE: Our previous study demonstrated that persimmon (Diospyros kaki Thumb.) at different stages of ripening provided different protective effects against high-fat/cholesterol diet (HFD)-induced dyslipidemia in rats. In this study, we compared the metabolites profile and gene expressions related to triglyceride (TG)/cholesterol metabolism in vitro and in vivo after treating with persimmon water extracts (PWE) or tannin-enriched persimmon concentrate (TEP). METHODS: Primary and secondary metabolites in test materials were determined by GC-TOF/MS, UHPLC-LTQ-ESI-IT-MS/MS, and UPLC-Q-TOF-MS. The expression of genes related to TG and cholesterol metabolism were determined by RT-PCR both in HepG2 cells stimulated by oleic acid/palmitic acid and in liver tissues obtained from Wistar rats fed with HFD and PWE at 0, 150, 300, and 600 mg/d (experiment I) or TEP at 0, 7, 14, and 28 mg/d (experiment II) by oral gavage for 9 weeks. RESULTS: PLS-DA analysis and heatmap analysis demonstrated significantly differential profiling of metabolites of PWE and TEP according to processing of persimmon powder. In vitro, TEP showed similar hypolipidemic effects as PWE, but significantly enhanced hypocholesterolemic effects compared to PWE in sterol regulatory element-binding protein 2 (SREBP2), HMG-CoA reductase (HMGCR), proprotein convertase subtilisin/kexin type 9 (PCSK9), cholesterol 7α-hydroxylase (CYP7A1), and low density lipoprotein receptor (LDLR) gene expression. Consistently, TEP and PWE showed similar hypolipidemic capacity in vivo, but significantly enhanced hypocholesterolemic capacity in terms of SREBP2, HMGCR, and bile salt export pump (BSEP) gene expression. CONCLUSION: These results suggest that column extraction after hot water extraction may be a good strategy to enhance tannins and long-chain fatty acid amides, which might cause stimulation of hypocholesterolemic actions through downregulation of cholesterol biosynthesis gene expression and upregulation of LDL receptor gene expression.

Screening of LDLR gene mutations in nine patients with familial hypercholesterolemia / 中华医学遗传学杂志

OBJECTIVE@#To screen for LDLR gene mutations in 9 patients with familial hypercholesterolemia (FH).@*METHODS@#All exons of the LDLR gene and flanking intronic sequences were amplified by PCR and subjected to automatic DNA sequencing. For patients with homozygous or compound heterozygous mutations, parental DNA sequencing or T cloning sequencing was carried out to determine the parental origin of the mutant alleles.@*RESULTS@#Direct sequencing of PCR products revealed 8 LDLR variants in 7 patients, which included c.259T>G, c.513delC, c.530C>T, c.682G>T, c.763C>T, c.1187-10G>A, c.1948delG, and c.1730G>A, among which c.1948delG was novel. Four patients have carried heterozygous mutations, two carried homozygous mutations, and one carried compound heterozygous mutations. The patients with biallelic mutations presented with a more severe phenotype compared those carrying heterozygous mutations.@*CONCLUSION@#LDLR mutations were identified in 7 out of 9 patients with FH. Among the 8 identified LDLR mutations, c.1948delG was firstly reported. Above findings have expanded the mutation spectrum of LDLR gene.

Serum Levels of PCSK9 Are Associated with Coronary Angiographic Severity in Patients with Acute Coronary Syndrome

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a circulating protein that promotes degradation of the low density lipoprotein receptor. PCSK9 has emerged as a target for lipid-lowering therapy, but the predictive value of the serum level of PCSK9 for the severity of coronary disease is largely unknown. METHODS: From December 2009 to July 2012, 121 individuals who underwent coronary angiography (CAG) because of clinically suspected acute coronary syndrome were enrolled in this study. Serum levels of PCSK9 and metabolic parameters were measured. SYNTAX (SYNergy between percutaneous coronary intervention with [paclitaxel-eluting] TAXUS stent and cardiac surgery) and GRACE (Global Registry of Acute Coronary Events) scores were calculated. RESULTS: Individuals with CAG lesions (n=100) had significantly higher levels of PCSK9 than those without lesions (n=21). The study population was stratified into three groups according to serum levels of PCSK9. The odds radio for occurrence of one or more CAG lesions was significantly higher in the group with the highest level of PCSK9 (odds ratio, 7.468; P=0.011) than in the group with the lowest level of PCSK9. Serum PCSK9 was positively associated with the number of involved coronary arteries. Multivariable linear regression indicated that levels of PCSK9 were positively correlated with GRACE risk scores and SYNTAX scores. CONCLUSION: Serum PCSK9 concentrations are higher in patients with coronary artery lesions, and are associated with SYNTAX and GRACE scores, suggesting that PCSK9 is a potential biomarker of the severity of coronary artery disease.

Genetic analysis of Iranian patients with familial hypercholesterolemia

Background: Familial hypercholesterolemia [FH] is a frequent autosomal dominant disorder of lipoprotein metabolism. This disorder is generally caused by mutations in low-density lipoprotein receptor [LDLR], apolipoprotein B 100 [APOB], and proprotein convertase subtilisin/kexin type 9 [PCSK9] genes. In the present study, we aimed at identifying the common LDLR and APOB gene mutations in an Iranian population

Methods: Eighty unrelated Iranian patients with FH entered the study, based on Simon Broome diagnostic criteria. All samples were screened for two common APOB gene mutations, including R3500Q and R3500W, by the means of ARMS-PCR and PCR- RFLP assays, respectively. In addition, exons 3, 4, 9, and 10 of LDLR gene were sequenced in all patients

Results: A novel mutation in exon 3 [C95W] and a previously described mutation in exon 4 [D139H] of LDLR gene were found. Three previously reported polymorphisms in LDLR gene as well as three novel polymorphisms were detected in the patients. However, in the studied population, no common mutations were observed in APOB gene

Conclusion: The results of our study imply that the genetic basis of FH in Iranian patients is different from other populations

Statin and the risk of new-onset diabetes mellitus

Statins are the first choice of pharmacological treatment for dyslipidemia to prevent atherosclerotic cardiovascular disease. Ample evidence demonstrates the benefits and safety of statin, including the lipid-lowering efficacy and the ability to improve clinical prognosis. High-intensity statin therapy is especially recommended in high-risk patients and those with cardiovascular disease. However, clinical trials, meta-analyses, and retrospective analyses have shown 9% to 13% increase in the risk of new-onset diabetes with statin therapy. The risk of new-onset diabetes with statin increased with higher statin doses, and the mechanisms are not yet fully understood. Mendelian randomization studies have suggested that new-onset diabetes with statin may be related to the activity of 3-hydroxy-3-methylglutaryl-coenzyme A reductase or low density lipoprotein receptor. Patients with familial hypercholesterolemia did not show an increased risk of new-onset diabetes with statin compared to their unaffected relatives. Moreover, some studies have shown that different kinds of statins impaired pancreatic beta-cell function. Recently, genetic analysis studies have shown probable associations between changes in several proteins involving lipid metabolism and the increased risk of new-onset diabetes. Statin therapy should be emphasized to prevent and treat atherosclerotic cardiovascular disease on the basis of individual cardiovascular risk and clinical characteristics, especially in high-risk patients, such as those with diabetes. It is important to combine statin therapy with patient education and lifestyle modifications, including diet control, exercise, and weight changes, to manage dyslipidemia and minimize the risk of new-onset diabetes. Statin therapy should be considered more important and the risk of new-onset diabetes with statin should not be overemphasized.

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.

Soy milk versus simvastatin for preventing atherosclerosis and left ventricle remodeling in LDL receptor knockout mice

Functional food intake has been highlighted as a strategy for the prevention of cardiovascular diseases by reducing risk factors. In this study, we compared the effects of oral treatment with soy milk and simvastatin on dyslipidemia, left ventricle remodeling and atherosclerotic lesion of LDL receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month old male LDLr-/- mice were distributed into four groups: control group (C), in which animals received standard diet; HL group, in which animals were fed a hyperlipidic diet; HL+SM or HL+S groups, in which animals were submitted to a hyperlipidic diet plus soy milk or simvastatin, respectively. After 60 days, both soy milk and simvastatin treatment prevented dyslipidemia, atherosclerotic lesion progression and left ventricle hypertrophy in LDLr-/- mice. These beneficial effects of soy milk and simvastatin were associated with reduced oxidative stress and inflammatory state in the heart and aorta caused by the hyperlipidic diet. Treatment with soy milk was more effective in preventing HDLc reduction and triacylglycerol and VLDLc increase. On the other hand, simvastatin was more effective in preventing an increase in total cholesterol, LDLc and superoxide production in aorta, as well as CD40L both in aorta and left ventricle of LDLr-/-. In conclusion, our results suggest a cardioprotective effect of soy milk in LDLr-/- mice comparable to the well-known effects of simvastatin.

Polimorfismos de los genes LEP , LDLR , APOA4 y sus relaciones con el sobrepeso, la obesidad y el riesgo de enfermedades crónicas en adultos del estado Sucre, Venezuela / LEP , LDLR and APOA4 gene polymorphisms and their relationship with the risk of overweight, obesity and chronic diseases in adults of the State of Sucre, Venezuela

Introducción. La prevalencia del sobrepeso, la obesidad y algunas enfermedades crónicas no transmisibles ha aumentado; sus causas pueden ser genéticas, epigenéticas o ambientales, por lo cual es importante evaluar la variabilidad en estas interacciones. Objetivo. Analizar las relaciones entre nueve polimorfismos de nucleótido simple de los genes LEP (rs2167270), LDLR (rs885765, rs688, rs5925, rs55903358, rs5742911) y APOA4 (rs5095, rs675, rs5110), y los fenotipos asociados al sobrepeso, la obesidad y otras enfermedades concomitantes. Materiales y métodos. Se evaluaron parámetros clínicos y antropométricos en 144 sujetos del estado Sucre, Venezuela, 76 hombres y 68 mujeres , con medias de edad de 29,93±8,29 y 32,49±11,15 años, respectivamente. Se hizo la genotipificación de los polimorfismos seleccionados mediante enzimas de restricción; se estudiaron las asociaciones entre genotipo y riesgo, y se compararon los promedios de las medidas antropométricas y bioquímicas previamente ajustadas a variables biológicas y ambientales. Resultados. Según el índice de masa corporal (IMC), el 38,9 % de los individuos tenía sobrepeso (25=IMC=29,9 kg/m 2 ) y el 20,1 %, obesidad (IMC=30 kg/m 2 ) . Las frecuencias genotípicas y alélicas de los grupos con un índice de masa corporal normal y uno alto (sobrepeso y obesidad) resultaron similares. Solo se encontró asociación entre el genotipo ancestral A/A del rs5742911 y el riesgo alto por los niveles de la lipoproteína de alta densidad o colesterol HDL (OR=2,944, IC 95% 1,446-5,996; p=0,003). La diferencia entre los promedios corregidos de colesterol HDL para los genotipos del rs5742911 resultó significativa (p=0,005) (A/A: 41,50±14,81 mg/dl; A/G: 45,00±12,07 mg/dl; G/G: 47,17±9,43 mg/dl). Conclusión. En la mayoría de las variantes genéticas estudiadas, se registró la asociación con el sobrepeso y la obesidad de los genotipos ancestrales, aunque sin ser significativa. El polimorfismo rs5742911 podría resultar útil como indicador del riesgo de enfermedades crónicas.

Introduction: Overweight, obesity and some chronic diseases have become more prevalent recently. It is well known that their causes may be genetic, epigenetic, environmental, or a mixture of these. Objective: To analyze the relationship between nine single nucleotide polymorphisms of genes LEP (rs2167270) , LDLR (rs885765, rs688, rs5925, rs55903358, rs5742911) and APOA4 (rs5095, rs675, rs5110) with obesity-related phenotypes and other comorbidities. Material and methods: We recruited 144 adults (76 males and 68 females, with average ages of 29.93±8.29 and 32.49±11.15 years, respectively) in the State of Sucre, Venezuela. Clinical and anthropometric parameters were obtained. Genotype-risk associations were studied. We then compared the averages registered for anthropometric and biochemical variables previously adjusted for biological and environmental factors. Results: According to the body mass index, 38.9% of the individuals in the sample were overweight (25=BMI=29.9 kg/m 2 ) and 20.1% were obese (BMI=30 kg/m 2 ). Genotype and allele frequencies did not differ statistically for groups with normal and high body mass index (overweight plus obesity). The association between LDLR rs5742911 ancestral genotype A/A and high risk condition related to HDL-cholesterol was the only one found to be significant (OR=2.944, 95% CI: 1.446-5.996; p=0.003). The difference in adjusted mean HDL-cholesterol for LDLR rs5742911 genotypes was statistically significant (p=0.005) (A/A: 41.50±14.81 mg/dL; A/G: 45.00±12.07 mg/dL; G/G: 47.17±9.43 mg/dL). Conclusions: For most of the genetic variants studied, there was an association with the presence of overweight and obesity among ancestral genotype carriers, although this was not statistically significant. The rs5742911 polymorphism may be useful as an indicator of a risk of chronic diseases.

Short- and long-term effects of xuezhikang, an extract of cholestin, on serum proprotein convertase subtilisin/kexin type 9 levels / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the short- and long-term effects of Xuezhikang (XZK), an extract of cholestin, on proprotein convertase subtilisin/kexin type 9 (PCSK9) level.</p><p><b>METHODS</b>Thirty rats were randomly divided into three groups and were given saline, XZK 1,200 mg/kg or lovastatin 10 mg/kg respectively by daily gavage for 3 days (n=10 for each). Sixteen patients without previous lipid-lowering drug treatment for dyslipidemia received XZK 1,200 mg daily for 8 weeks. Fasting blood samples and liver tissue were collected at day 3 for rats, while the blood samples were obtained at baseline and week 8 from patients. The serum PCSK9 and lipid profile were measured. The expression of hepatic low density lipoprotein (LDL) receptor and sterol regulatory element binding protein 2 (SREBP-2) were measured by real time-PCR.</p><p><b>RESULTS</b>PCSK9 levels in rats were significantly increased in the XZK and lovastatin groups (P=0.002, P=0.003 vs. control) at day 3, while no significant differences were found in the levels of lipid parameters. PCSK9 levels in patients increased by 34% (P=0.006 vs. baseline) accompanied by total cholesterol and LDL-cholesterol decreased by 22% and 28% P=0.001, P=0.002 vs. baseline). The hepatic mRNA levels of LDL-receptor and SREBP-2 were significantly increased in the XZK and lovastatin groups.</p><p><b>CONCLUSION</b>XZK has significant impact on PCSK9 in a short- and long-term manner in both rats and humans. Moreover, the data indicated that as lovastatin, XZK increased PCSK9 levels through SREBP-2 pathway.</p>

APOE and LDLR Gene Polymorphisms and Dyslipidemia Tracking. Rio de Janeiro Study / Polimorfismos dos Genes APOE e RLDL e Tracking de Dislipidemia em Jovens. Estudo do Rio de Janeiro

Background: Studies show an association between changes in apolipoprotein E (ApoE) and LDLR receptor with the occurrence of dyslipidemia. Objectives: To investigate the association between polymorphisms of the APOE (ε2, ε3, ε4) and LDLR (A370T) genes with the persistence of abnormal serum lipid levels in young individuals followed up for 17 years in the Rio de Janeiro Study. Methods: The study included 56 individuals (35 males) who underwent three assessments at different ages: A1 (mean age 13.30 ± 1.53 years), A2 (22.09 ± 1.91 years) and A3 (31.23 ± 1.99 years). Clinical evaluation with measurement of blood pressure (BP) and body mass index (BMI) was conducted at all three assessments. Measurement of waist circumference (WC) and serum lipids, and analysis of genetic polymorphisms by PCR-RFLP were performed at A2 and A3. Based on dyslipidemia tracking, three groups were established: 0 (no abnormal lipid value at A2 and A3), 1 (up to one abnormal lipid value at A2 or A3) and 2 (one or more abnormal lipid values at A2 and A3). Results: Compared with groups 0 and 1, group 2 presented higher mean values of BP, BMI, WC, LDL-c and TG (p < 0.01) and lower mean values of HDL-c (p = 0.001). Across the assessments, all individuals with APOE genotypes ε2/ε4 and ε4/ε4 maintained at least one abnormal lipid variable, whereas those with genotype ε2/ε3 did not show abnormal values (χ2 = 16.848, p = 0.032). For the LDLR genotypes, there was no significant difference among the groups. Conclusions: APOE gene polymorphisms were associated with dyslipidemia in young individuals followed up longitudinally from childhood. .

Fundamento: Estudos demonstram a associação de alterações da apolipoproteína E (APOE) e do receptor da RLDL com a ocorrência de dislipidemia. Objetivos: Investigar a associação entre polimorfismos dos genes da APOE (APOE - ε2, ε3, ε4) e do receptor da LDL (RLDL - A370T) com a persistência de alterações dos níveis lipídicos séricos em jovens acompanhados há 17 anos no Estudo do Rio de Janeiro. Métodos: Foram estudados 56 indivíduos (35 masculinos) em três avaliações realizadas em idades distintas: A1 – média de idade: 13,30 ± 1,53 anos; A2 – média de idade: 22,09±1,91 anos e A3 – média de idade: 31,23±1,99 anos. Nas três avaliações foram determinados a pressão arterial (PA) e o índice de massa corporal (IMC). Em A2 e A3 foram obtidos a circunferência abdominal (CA) e os lípides séricos, e analisados os polimorfismos genéticos por PCR-RFLP. Com base no tracking de dislipidemia, três grupos foram constituídos: 0 (nenhum lípide alterado em A2 e A3), 1 (até um lípide alterado em A2 ou A3) e 2 (um ou mais lípides alterados em A2 e A3). Resultados: Em comparação aos grupos 0 e 1, o grupo 2 apresentou maiores médias de PA, IMC, CA, LDL-c e TG (p < 0,01) e menor média de HDL-c (p = 0,001) que os grupos 0 e 1. Todos os indivíduos com genótipo APOE ε2/ε4 e ε4/ε4 mantiveram durante as avaliações pelo menos um lípide alterado, enquanto que aqueles com genótipo ε2/ε3 não apresentaram alterações (χ2=16,848, p = 0,032). Para os genótipos RLDL não houve diferença significativa entre os grupos. Conclusões: O polimorfismo do gene APOE se associou à presença de dislipidemia em indivíduos jovens em acompanhamento longitudinal desde a infância. .

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.

Regulatory effect of coptisine on key genes involved in cholesterol metabolism / 中国中药杂志

To study the effect of cholesterol and 25-OH-cholesterol on cholesterol metabolism in HepG2 cells and the effect of coptisine (Cop) extracted from Coptidis Rhizoma (CR) in reducing and regulating cholesterol. In this study, TC, TG, LDL-c and HDL-c were measured by biochemical analysis; mRNA and protein expressions of LDLR, HMGCR and CYP7A1 were detected by qRT-PCR and Western blot. According to the results, cholesterol and 25-OH-cholesterol inducing could decrease in mRNA and protein expressions of LDLR and CYP7A1, so as to increase TC and LDL-c contents. However, Cop could up-regulate mRNA and protein expressions of LDLR and CYP7A1 and down-regulate that of HMGCR, so as to reduce TC and LDL-c levels. These findings suggested that Cop has potential pharmacological activity for reducing cholesterol, and may reduce cholesterol by regulating mRNA and protein expressions of key genes involved in cholesterol metabolism, such as LDLR, CYP7A1 and HMGCR. This study laid a firm theoretical foundation for developing new natural drugs with the cholesterol-lowering activity.