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1.
Clin Chim Acta ; 520: 71-75, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34052205

RESUMO

Dysbetalipoproteinemia (DBL) is an uncommon condition characterized by a mixed hyperlipidemia due to accumulation of remnant lipoproteins and is highly atherogenic. Typically, DBL is an autosomal recessive condition requiring an additional metabolic stress with reduced apolipoprotein E (apoE) function. However, DBL is also described in patients with multiple myeloma without the characteristic apoE2/E2 mutation seen in familial DBL. Although the underlying pathogenesis in these cases is not fully characterized, it is thought to occur due to interference with apoE function by antibodies produced from clonal plasma cells. Such cases are referred to as hyperlipidemic myeloma (HLM) and have rarely been described in the literature. To our knowledge there is no prior description of HLM in HIV positive patients in Africa. We describe a case of HLM in an African woman with underlying HIV infection who presented with phenotypic and biochemical features of DBL that responded poorly to lipid lowering therapy.


Assuntos
Infecções por HIV , Hiperlipoproteinemia Tipo III , Mieloma Múltiplo , África , Apolipoproteína E2 , Apolipoproteínas E , Feminino , Humanos , Hiperlipoproteinemia Tipo III/genética , Triglicerídeos
2.
Arterioscler Thromb Vasc Biol ; 41(2): 934-943, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33147992

RESUMO

OBJECTIVE: Familial hypercholesterolemia (FH) is characterized by elevated low-density lipoprotein-cholesterol and markedly increased cardiovascular risk. In patients with a genetic diagnosis, low-density lipoprotein receptor (LDLR) mutations account for >90% of cases, apolipoprotein B (APOB) mutations for ≈5% of cases, while proprotein convertase subtilisin kexin type 9 (PCSK9) gain of function mutations are rare (<1% of cases). We aimed to evaluate the functional impact of several novel PCSK9 variants in a cohort of patients with FH by genetic cascade screening and in vitro functionality assays. Approach and Results: Patients with clinically diagnosed FH underwent genetic analysis of LDLR, and if negative, sequential testing of APOB and PCSK9. We analyzed cosegregation of hypercholesterolemia with novel PCSK9 variants. Gain of function status was determined by in silico analyses and validated by in vitro functionality assays. Among 1055 persons with clinical FH, we identified nonsynonymous PCSK9 variants in 27 (2.6%) patients and 7 of these carried one of the 4 previously reported gain of function variants. In the remaining 20 patients with FH, we identified 7 novel PCSK9 variants. The G516V variant (c.1547G>T) was found in 5 index patients and cascade screening identified 15 additional carriers. Low-density lipoprotein-cholesterol levels were higher in these 15 carriers compared with the 27 noncarriers (236±73 versus 124±35 mg/dL; P<0.001). In vitro studies demonstrated the pathogenicity of the G516V variant. CONCLUSIONS: In our study, 1.14% of cases with clinical FH were clearly attributable to pathogenic variants in PCSK9. Pathogenicity is established beyond doubt for the G516V variant.


Assuntos
Hiperlipoproteinemia Tipo II/genética , Mutação , Pró-Proteína Convertase 9/genética , Adulto , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Células HEK293 , Fatores de Risco de Doenças Cardíacas , Células Hep G2 , Hereditariedade , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/diagnóstico , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Intervalo Livre de Progressão , Pró-Proteína Convertase 9/metabolismo , Medição de Risco , África do Sul , Fatores de Tempo , Adulto Jovem
3.
Curr Atheroscler Rep ; 21(12): 48, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31741187

RESUMO

PURPOSE OF REVIEW: The goal of this review is to evaluate the role of inhibiting the synthesis of lipoproteins when there is no or little residual LDL-receptor function as in patients with homozygous familial hypercholesterolaemia. Lomitapide is administered orally once a day while mipomersen is given by subcutaneous injection once a week. Lomitapide inhibits microsomal triglyceride transfer protein while mipomersen is an antisense oligonucleotide directed against apoB100. RECENT FINDINGS: The pivotal registration trials for lomitapide and mipomersen were published in 2013 and 2010, respectively. More recently published data from extension trials and cohort studies provides additional information on long-term safety and efficacy. The mean LDL cholesterol reduction was 50% with lomitapide in its single-arm open-label registration trial. Mipomersen reduced LDL cholesterol by approximately 25% in its double-blind, placebo-controlled registration study. Both lomitapide and mipomersen therapy are associated with variable increases in hepatic fat content. The long-term safety of increased hepatic fat content in patients receiving these therapies is uncertain and requires further study. Both drugs may cause elevated transaminase in some patients, but no cases of severe liver injury have been reported. Lomitapide may also cause gastrointestinal discomfort and diarrhoea, especially if patients consume high-fat meals and patients are advised to follow a low-fat diet supplemented with essential fatty acids and fat-soluble vitamins. Mipomersen may cause injection-site and influenza-like reactions. The effect of lomitapide and mipomersen on cardiovascular outcomes has not been studied, but circumstantial evidence suggests that the LDL cholesterol lowering achieved with these two agents may reduce cardiovascular event rates.


Assuntos
Apolipoproteína B-100/biossíntese , Benzimidazóis/farmacologia , Hiperlipoproteinemia Tipo II , Oligonucleotídeos/farmacologia , Anticolesterolemiantes/farmacologia , Doenças Cardiovasculares/prevenção & controle , Proteínas de Transporte/antagonistas & inibidores , Humanos , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/metabolismo , Microssomos
4.
J Clin Lipidol ; 13(2): 287-300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30797720

RESUMO

BACKGROUND: There is a lack of information on the health care of familial hypercholesterolemia (FH). OBJECTIVE: The objective of this study was to compare the health care of FH in countries of the Asia-Pacific region and Southern Hemisphere. METHODS: A series of questionnaires were completed by key opinion leaders from selected specialist centers in 12 countries concerning aspects of the care of FH, including screening, diagnosis, risk assessment, treatment, teaching/training, and research; the United Kingdom (UK) was used as the international benchmark. RESULTS: The estimated percentage of patients diagnosed with the condition was low (overall <3%) in all countries, compared with ∼15% in the UK. Underdetection of FH was associated with government expenditure on health care (Ï° = 0.667, P < .05). Opportunistic and systematic screening methods, and the Dutch Lipid Clinic Network criteria were most commonly used to detect FH; genetic testing was infrequently used. Noninvasive imaging of coronary calcium and/or carotid plaques was underutilized in risk assessment. Patients with FH were generally not adequately treated, with <30% of patients achieving guideline recommended low-density lipoprotein cholesterol targets on conventional therapies. Treatment gaps included suboptimal availability and use of lipoprotein apheresis and proprotein convertase subtilsin-kexin type 9 inhibitors. A deficit of FH registries, training programs, and publications were identified in less economically developed countries. The demonstration of cost-effectiveness for cascade screening, genetic testing, and specialized treatments were significantly associated with the availability of subsidies from the health care system (Ï° = 0.571-0.800, P < .05). CONCLUSION: We identified important gaps across the continuum of care for FH, particularly in less economically developed countries. Wider implementation of primary and pediatric care, telehealth services, patient support groups, education/training programs, research activities, and health technology assessments are needed to improve the care of patients with FH in these countries.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Hiperlipoproteinemia Tipo II/epidemiologia , Remoção de Componentes Sanguíneos , Doenças Cardiovasculares/complicações , LDL-Colesterol/sangue , Atenção à Saúde/economia , Dietoterapia , Custos de Cuidados de Saúde/estatística & dados numéricos , Educação em Saúde , Humanos , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/economia , Hiperlipoproteinemia Tipo II/terapia , Reembolso de Seguro de Saúde , Internacionalidade , Inibidores de PCSK9 , Sistema de Registros , Medição de Risco , Inibidores de Serina Proteinase/farmacologia , Inibidores de Serina Proteinase/uso terapêutico
5.
Pathology ; 51(2): 165-176, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30598326

RESUMO

Apolipoprotein E (apoE), a 34 kDa circulating glycoprotein of 299 amino acids, predominantly synthesised in the liver, associates with triglyceride-rich lipoproteins to mediate the clearance of their remnants after enzymatic lipolysis in the circulation. Its synthesis in macrophages initiates the formation of high density-like lipoproteins to effect reverse cholesterol transport to the liver. In the nervous system apoE forms similar lipoproteins which perform the function of distributing lipids amongst cells. ApoE accounts for much of the variation in plasma lipoproteins by three common variants (isoforms) that influence low-density lipoprotein concentration and the risk of atherosclerosis. ApoE2 generally is most favourable and apoE4 least favourable for cardiovascular and neurological health. The apoE variants relate to different amino acids at positions 112 and 158: cysteine in both for apoE2, arginine at both sites for apoE4, and respectively cysteine and arginine for apoE3 that is viewed as the wild type. Paradoxically, under metabolic stress, homozygosity for apoE2 may result in dysbetalipoproteinaemia in adults owing to impaired binding of remnant lipoproteins to the LDL receptor and related proteins as well as heparan sulphate proteoglycans. This highly atherogenic condition is also seen with other mutations in apoE, but with autosomal dominant inheritance. Mutations in apoE may also cause lipoprotein glomerulopathy. In the central nervous system apoE binds amyloid ß-protein and tau protein and fragments may incur cellular damage. ApoE4 is a strong risk factor for the development of Alzheimer's disease. ApoE has several other physiological effects that may influence health and disease, including supply of docosahexaenoic acid for the brain and modulating immune and inflammatory responses. Genotyping of apoE may have application in disorders of lipoprotein metabolism as well as glomerulopathy and may be relevant to personalised medicine in understanding cardiovascular risk, and the outcome of nutritional and therapeutic interventions. Quantitation of apoE will probably not be clinically useful. ApoE is also of interest as it may generate peptides with biological function and could be employed in nanoparticles that may allow crossing of the blood-brain barrier. Therapeutic options may emerge from these newer insights.


Assuntos
Apolipoproteínas E/metabolismo , Doenças Cardiovasculares/metabolismo , Dislipidemias/metabolismo , Metabolismo dos Lipídeos , Lipoproteínas/metabolismo , Sistema Nervoso/metabolismo , Peptídeos beta-Amiloides/metabolismo , Apolipoproteína E2/genética , Apolipoproteína E2/metabolismo , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Apolipoproteínas E/genética , Doenças Cardiovasculares/fisiopatologia , Dislipidemias/fisiopatologia , Saúde , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Lipoproteínas/genética , Fígado/metabolismo , Sistema Nervoso/fisiopatologia , Isoformas de Proteínas , Receptores de LDL/genética , Receptores de LDL/metabolismo , Fatores de Risco
6.
Atherosclerosis ; 277: 234-255, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30270054

RESUMO

BACKGROUND AND AIMS: Management of familial hypercholesterolaemia (FH) may vary across different settings due to factors related to population characteristics, practice, resources and/or policies. We conducted a survey among the worldwide network of EAS FHSC Lead Investigators to provide an overview of FH status in different countries. METHODS: Lead Investigators from countries formally involved in the EAS FHSC by mid-May 2018 were invited to provide a brief report on FH status in their countries, including available information, programmes, initiatives, and management. RESULTS: 63 countries provided reports. Data on FH prevalence are lacking in most countries. Where available, data tend to align with recent estimates, suggesting a higher frequency than that traditionally considered. Low rates of FH detection are reported across all regions. National registries and education programmes to improve FH awareness/knowledge are a recognised priority, but funding is often lacking. In most countries, diagnosis primarily relies on the Dutch Lipid Clinics Network criteria. Although available in many countries, genetic testing is not widely implemented (frequent cost issues). There are only a few national official government programmes for FH. Under-treatment is an issue. FH therapy is not universally reimbursed. PCSK9-inhibitors are available in ∼2/3 countries. Lipoprotein-apheresis is offered in ∼60% countries, although access is limited. CONCLUSIONS: FH is a recognised public health concern. Management varies widely across countries, with overall suboptimal identification and under-treatment. Efforts and initiatives to improve FH knowledge and management are underway, including development of national registries, but support, particularly from health authorities, and better funding are greatly needed.


Assuntos
Anticolesterolemiantes/uso terapêutico , Remoção de Componentes Sanguíneos , Saúde Global , Hiperlipoproteinemia Tipo II/terapia , Cooperação Internacional , Anticolesterolemiantes/efeitos adversos , Biomarcadores/sangue , Remoção de Componentes Sanguíneos/efeitos adversos , LDL-Colesterol/sangue , Comportamento Cooperativo , Predisposição Genética para Doença , Pesquisas sobre Atenção à Saúde , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Fenótipo , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Resultado do Tratamento
7.
Atherosclerosis ; 277: 327-333, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30270067

RESUMO

BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is characterized by markedly increased LDL-cholesterol (LDL-C) and premature cardiovascular disease (CVD). LDL-C lowering is the cornerstone of therapy. The aim of our study was to evaluate LDL-C target achievement and explore reasons for not reaching target in FH patients attending a public-sector lipid clinic at Groote Schuur Hospital in Cape Town, South Africa. METHODS: We reviewed clinical records of patients with genetically confirmed heterozygous FH (heFH) retrospectively. For patients seen after 2013, when new guidelines were published, we determined reasons for use of submaximal therapy. RESULTS: Our study population consisted of 776 adult heFH patients. A substantial proportion (41%) of those younger than 50 years of age had already experienced a cardiovascular event. The mean (±SD) untreated and best achieved LDL-C values during follow up were 8.1 ±â€¯2.1 and 4.0 ±â€¯1.5 mmol/l, respectively. Despite a mean LDL-C reduction of 50%, only 140 (25%) achieved an LDL-C ≤ 3.0 mmol/l. Of the 164 participants with follow up after 2013, 42 did not reach LDL-C < 3.0 mmol/l and did not use maximal therapy (26%). The commonest reasons for not using maximum therapy were statin side-effects (n = 15, 36%) and acceptance by the patient (n = 9, 22%) or the physician (n = 8, 19%) of the control achieved. CONCLUSIONS: The heFH population in Cape Town is characterized by high baseline LDL-C, a high prevalence of CVD at presentation and low rates of achieving an LDL-C target of 3.0 mmol/l.


Assuntos
Anticolesterolemiantes/uso terapêutico , LDL-Colesterol/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Adulto , Anticolesterolemiantes/efeitos adversos , Biomarcadores/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Regulação para Baixo , Quimioterapia Combinada , Ezetimiba/uso terapêutico , Feminino , Predisposição Genética para Doença , Hereditariedade , Heterozigoto , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/genética , Masculino , Pessoa de Meia-Idade , Inibidores de PCSK9 , Linhagem , Fenótipo , Prevalência , Pró-Proteína Convertase 9/metabolismo , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Inibidores de Serina Proteinase/uso terapêutico , África do Sul/epidemiologia , Fatores de Tempo , Resultado do Tratamento
8.
Eur Heart J ; 39(14): 1162-1168, 2018 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-29106543

RESUMO

Aims: Homozygous familial hypercholesterolaemia (FH) is a rare inherited disorder characterized by extreme hypercholesterolaemia from birth, accelerated atherosclerosis, and premature death. Many forms of lipid-lowering therapies have been used in the past, but definitive evidence of benefit has been lacking. We therefore undertook a retrospective survey of lipid levels and clinical outcomes of FH homozygotes treated with a combination of lipid-lowering measures between 1990 and 2014 in South Africa and the UK. Methods and results: We divided 133 previously statin-naive homozygotes into quartiles according to their on-treatment levels of serum cholesterol and compared the occurrence of any death, cardiovascular death, and major adverse cardiovascular events (MACE) between the quartiles during 25 years of follow-up, using Cox and competing risks regression analysis. Patients in Quartile 4, with an on-treatment serum cholesterol >15.1 mmol/L, had a hazard ratio of 11.5 for any death compared with those in Quartile 1, with an on-treatment cholesterol of < 8.1 mmol/L. Those in Quartiles 2 and 3 combined, with on-treatment cholesterol of 8.1-15.1 mmol/L had a hazard ratio of 3.6 compared with Quartile 1. These differences were statistically significant (P < 0.001) and remained so after adjustments for confounding factors (P = 0.04). Significant differences between quartiles were also evident for cardiovascular deaths and MACE. Conclusion: These findings provide unequivocal evidence that the extent of reduction of serum cholesterol achieved by a combination of therapeutic measures, including statins, ezetimibe, lipoprotein apheresis, and evolocumab, is a major determinant of survival in homozygous FH.


Assuntos
Colesterol/sangue , Hiperlipoproteinemia Tipo II/mortalidade , Adolescente , Adulto , Anticolesterolemiantes/uso terapêutico , Feminino , Homozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/genética , Estimativa de Kaplan-Meier , Masculino , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
9.
Curr Opin Endocrinol Diabetes Obes ; 24(2): 133-139, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28098593

RESUMO

PURPOSE OF REVIEW: To review pathophysiological, epidemiological and clinical aspects of familial dysbetalipoproteinemia; a model disease for remnant metabolism and remnant-associated cardiovascular risk. RECENT FINDINGS: Familial dysbetalipoproteinemia is characterized by remnant accumulation caused by impaired remnant clearance, and premature cardiovascular disease. Most familial dysbetalipoproteinemia patients are homozygous for apolipoprotein ε2, which is associated with decreased binding of apolipoprotein E to the LDL receptor. Although familial dysbetalipoproteinemia is an autosomal recessive disease in most cases, 10% is caused by autosomal dominant mutations. Of people with an ε2ε2 genotype 15% develops familial dysbetalipoproteinemia, which is associated with secondary risk factors, such as obesity and insulin resistance, that inhibit remnant clearance by degradation of the heparan sulfate proteoglycan receptor. The prevalence of familial dysbetalipoproteinemia ranges from 0.12 to 0.40% depending on the definition used. Clinical characteristics of familial dysbetalipoproteinemia are xanthomas and mixed hyperlipidemia (high total cholesterol and triglycerides); the primary lipid treatment goal in familial dysbetalipoproteinemia is non-HDL-cholesterol; and treatment consists of dietary therapy and treatment with statin and fibrate combination. SUMMARY: Familial dysbetalipoproteinemia is a relatively common, though often not diagnosed, lipid disorder characterized by mixed hyperlipidemia, remnant accumulation and premature cardiovascular disease, which should be treated with dietary therapy and statin and fibrate combination.


Assuntos
Erros de Diagnóstico/estatística & dados numéricos , Hiperlipoproteinemia Tipo III/diagnóstico , Hiperlipoproteinemia Tipo III/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/terapia , Dietoterapia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipoproteinemia Tipo III/etiologia , Hiperlipoproteinemia Tipo III/terapia , Lipoproteínas/sangue , Fatores de Risco , Triglicerídeos/sangue
10.
Atheroscler Suppl ; 22: 1-32, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27939304

RESUMO

BACKGROUND: The potential for global collaborations to better inform public health policy regarding major non-communicable diseases has been successfully demonstrated by several large-scale international consortia. However, the true public health impact of familial hypercholesterolaemia (FH), a common genetic disorder associated with premature cardiovascular disease, is yet to be reliably ascertained using similar approaches. The European Atherosclerosis Society FH Studies Collaboration (EAS FHSC) is a new initiative of international stakeholders which will help establish a global FH registry to generate large-scale, robust data on the burden of FH worldwide. METHODS: The EAS FHSC will maximise the potential exploitation of currently available and future FH data (retrospective and prospective) by bringing together regional/national/international data sources with access to individuals with a clinical and/or genetic diagnosis of heterozygous or homozygous FH. A novel bespoke electronic platform and FH Data Warehouse will be developed to allow secure data sharing, validation, cleaning, pooling, harmonisation and analysis irrespective of the source or format. Standard statistical procedures will allow us to investigate cross-sectional associations, patterns of real-world practice, trends over time, and analyse risk and outcomes (e.g. cardiovascular outcomes, all-cause death), accounting for potential confounders and subgroup effects. CONCLUSIONS: The EAS FHSC represents an excellent opportunity to integrate individual efforts across the world to tackle the global burden of FH. The information garnered from the registry will help reduce gaps in knowledge, inform best practices, assist in clinical trials design, support clinical guidelines and policies development, and ultimately improve the care of FH patients.


Assuntos
Prestação Integrada de Cuidados de Saúde , Hiperlipoproteinemia Tipo II/terapia , Cooperação Internacional , Lacunas da Prática Profissional , Sistema de Registros , Projetos de Pesquisa , Acesso à Informação , Comportamento Cooperativo , Mineração de Dados , Prestação Integrada de Cuidados de Saúde/organização & administração , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/mortalidade , Armazenamento e Recuperação da Informação , Objetivos Organizacionais , Resultado do Tratamento
11.
J Clin Lipidol ; 10(5): 1262-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27678445

RESUMO

Tendon xanthoma are most commonly associated with Familial Hypercholesterolemia, but the differential diagnosis includes sitosterolemia and cerebrotendinous xanthomatosis (CTX). The case presented here is of a 48-year old male with large tendon xanthomas attributable to CTX. CTX is a rare, recessive disorder caused by mutations in the CYP27A1 gene. The resultant defect in bile acid synthesis leads to cholestanol deposition in different tissues in the body, including tendons. CTX is associated with neurologic symptoms and a reduced life expectancy. Treatment consists of bile acid supplementation in combination with a statin. When patients present with tendon xanthomas and FH is ruled out, clinicians should consider CTX as a possible diagnosis.


Assuntos
Hiperlipoproteinemia Tipo II/diagnóstico , Tendões/patologia , Xantomatose/diagnóstico , Encéfalo/diagnóstico por imagem , Colestanotriol 26-Mono-Oxigenase/genética , Diagnóstico Diferencial , Humanos , Hiperlipoproteinemia Tipo II/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Xantomatose/complicações
12.
J Atheroscler Thromb ; 23(8): 891-900, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27384016

RESUMO

Familial hypercholesterolemia (FH) is the most common and serious form of inherited hyperlipidaemia. Dominantly inherited with high penetrance, untreated FH leads to premature death from coronary artery disease due to accelerated atherosclerosis from birth. Despite its importance, there is still a major shortfall in awareness, detection and treatment of FH worldwide. International models of care for FH have recently been published, but their effective implementation requires the garnering of more knowledge about the condition. The "Ten Countries Study" aims to investigate diagnostic, epidemiological and service aspects, as well as physician practices and patient experiences of FH in several countries in the Asia-Pacific Region and the Southern Hemisphere. Five observational studies are being undertaken that will systematically investigate the following aspects of FH: the phenotypic predictors of low-density lipoprotein receptor mutations, the point prevalence in available community populations, current knowledge and clinical practices among primary care physicians, availability and utilisation of services and facilities, and patient perceptions and personal experiences of the condition. The information gathered will inform better clinical practice and will enable the development of country-specific models of care for FH.


Assuntos
Hiperlipoproteinemia Tipo II/prevenção & controle , Qualidade da Assistência à Saúde/normas , Pesquisa Translacional Biomédica/normas , Humanos
13.
Circ Cardiovasc Genet ; 8(6): 823-31, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26374825

RESUMO

BACKGROUND: Patients with PCSK9 gene gain of function (GOF) mutations have a rare form of autosomal dominant hypercholesterolemia. However, data examining their clinical characteristics and geographic distribution are lacking. Furthermore, no randomized treatment study in this population has been reported. METHODS AND RESULTS: We compiled clinical characteristics of PCSK9 GOF mutation carriers in a multinational retrospective, cross-sectional, observational study. We then performed a randomized placebo-phase, double-blind study of alirocumab 150 mg administered subcutaneously every 2 weeks to 13 patients representing 4 different PCSK9 GOF mutations with low-density lipoprotein cholesterol (LDL-C) ≥70 mg/dL on their current lipid-lowering therapies at baseline. Observational study: among 164 patients, 16 different PCSK9 GOF mutations distributed throughout the gene were associated with varying severity of untreated LDL-C levels. Coronary artery disease was common (33%; average age of onset, 49.4 years), and untreated LDL-C concentrations were higher compared with matched carriers of mutations in the LDLR (n=2126) or apolipoprotein B (n=470) genes. Intervention study: in PCSK9 GOF mutation patients randomly assigned to receive alirocumab, mean percent reduction in LDL-C at 2 weeks was 62.5% (P<0.0001) from baseline, 53.7% compared with placebo-treated PCSK9 GOF mutation patients (P=0.0009; primary end point). After all subjects received 8 weeks of alirocumab treatment, LDL-C was reduced by 73% from baseline (P<0.0001). CONCLUSIONS: PCSK9 GOF mutation carriers have elevated LDL-C levels and are at high risk of premature cardiovascular disease. Alirocumab, a PCSK9 antibody, markedly lowers LDL-C levels and seems to be well tolerated in these patients. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique Identifier: NCT01604824.


Assuntos
Anticorpos Monoclonais/administração & dosagem , LDL-Colesterol/sangue , Doença da Artéria Coronariana , Hiperlipoproteinemia Tipo II , Mutação , Pró-Proteína Convertases , Serina Endopeptidases , Adolescente , Adulto , Idoso , Anticorpos Monoclonais Humanizados , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/genética , Método Duplo-Cego , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/genética , Masculino , Pessoa de Meia-Idade , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/antagonistas & inibidores , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
15.
J Am Coll Cardiol ; 63(22): 2365-73, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24632287

RESUMO

OBJECTIVES: Do elevated proprotein convertase subtilisin/kexin type 9 (PCSK9) levels constitute an even greater risk for patients who already have reduced low-density lipoprotein receptor (LDLR) levels, such as those with heterozygous familial hypercholesterolemia (HeFH)? BACKGROUND: As a circulating inhibitor of LDLR, PCSK9 is an attractive target for lowering LDL-cholesterol (LDL-C) levels. METHODS: Circulating PCSK9 levels were measured by enzyme-linked immunosorbent assay in nontreated patients with HeFH carrying a D206E (n = 237), V408M (n = 117), or D154N (n = 38) LDLR missense mutation and in normolipidemic controls (n = 152). Skin fibroblasts and lymphocytes were isolated from a subset of patients and grown in 0.5% serum and mevastatin with increasing amounts of recombinant PCSK9. LDLR abundance at the cell surface was determined by flow cytometry. RESULTS: PCSK9 reduced LDLR expression in a dose-dependent manner in control and FH fibroblasts to similar extents, by up to 77 ± 8% and 82 ± 7%, respectively. Likewise, PCSK9 reduced LDLR abundance by 39 ± 8% in nonfamilial hypercholesterolemia (non-FH) and by 45 ± 10% in HeFH lymphocytes, irrespective of their LDLR mutation status. We found positive correlations of the same magnitude between PCSK9 and LDL-C levels in controls (beta = 0.22; p = 0.0003), D206E (beta = 0.20; p = 0.0002), V408M (beta = 0.24; p = 0.0002), and D154N (beta = 0.25; p = 0.048) patients with HeFH. The strengths of these associations were all similar. CONCLUSIONS: Elevated PCSK9 levels are equally detrimental for patients with HeFH or non-FH: a 100-ng/ml increase in PCSK9 will lead to an increase in LDL-C of 0.20 to 0.25 mmol/l in controls and HeFH alike, irrespective of their LDLR mutation. This explains why patients with non-FH or HeFH respond equally well to monoclonal antibodies targeting PCSK9.


Assuntos
Hipercolesterolemia/sangue , Hiperlipoproteinemia Tipo II/sangue , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Adulto , Feminino , Heterozigoto , Humanos , Hipercolesterolemia/genética , Hiperlipoproteinemia Tipo II/genética , Masculino , Mutação , Pró-Proteína Convertase 9 , Receptores de LDL/genética
16.
J Infect Dis ; 209(5): 754-63, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24133190

RESUMO

BACKGROUND: Statins are cholesterol-lowering drugs, targeting HMG-CoA reductase, thereby reducing the risk of coronary disorders and hypercholesterolemia. However, they also can influence immunologic responses. METHODS: Peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages (MDMs) were isolated from patients with familial hypercholesterolemia (FH) during statin therapy. After infection of cells with Mycobacterium tuberculosis, bacterial burden was determined. In vivo, mice were treated with statins before aerosol-based infection with M. tuberculosis and were monitored for disease progression. RESULTS: PBMCs and MDMs from patients with FH receiving statin therapy were more resistant to M. tuberculosis infection, with reduced bacterial burdens, compared with those of healthy donors. Moreover, statin treatment in experimental murine M. tuberculosis infection studies increased host protection, with reduced lung burdens and improved histopathologic findings. Mechanistically, metabolic rescue experiments demonstrated that statins reduce membrane cholesterol levels, particularly by the mevalonate-isoprenoid arm of the sterol pathway. This promoted phagosomal maturation (EEA-1/Lamp-3) and autophagy (LC3-II), as shown by confocal microscopy and Western blot in macrophages. In addition, inhibitors of phagosome and autophagosome maturation reversed the beneficial effect of statins on bacterial growth. CONCLUSION: These results suggest that statin-mediated reduction in cholesterol levels within phagosomal membranes counteract M. tuberculosis-induced inhibition of phagosomal maturation and promote host-induced autophagy, thereby augmenting host protection against tuberculosis.


Assuntos
Autofagia/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Macrófagos/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Fagossomos/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Colesterol/metabolismo , Farmacorresistência Bacteriana/fisiologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Fagossomos/metabolismo , Fagossomos/microbiologia , Tuberculose/metabolismo , Tuberculose/microbiologia
17.
PLoS One ; 8(9): e75490, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086542

RESUMO

Statins are well-known cholesterol lowering drugs targeting HMG-CoA-reductase, reducing the risk of coronary disorders and hypercholesterolemia. Statins are also involved in immunomodulation, which might influence the outcome of bacterial infection. Hence, a possible effect of statin treatment on Listeriosis was explored in mice. Statin treatment prior to subsequent L. monocytogenes infection strikingly reduced bacterial burden in liver and spleen (up to 100-fold) and reduced histopathological lesions. Statin-treatment in infected macrophages resulted in increased IL-12p40 and TNF-α and up to 4-fold reduced bacterial burden within 6 hours post infection, demonstrating a direct effect of statins on limiting bacterial growth in macrophages. Bacterial uptake was normal investigated in microbeads and GFP-expressing Listeria experiments by confocal microscopy. However, intracellular membrane-bound cholesterol level was decreased, as analyzed by cholesterol-dependent filipin staining and cellular lipid extraction. Mevalonate supplementation restored statin-inhibited cholesterol biosynthesis and reverted bacterial growth in Listeria monocytogenes but not in listeriolysin O (LLO)-deficient Listeria. Together, these results suggest that statin pretreatment increases protection against L. monocytogenes infection by reducing membrane cholesterol in macrophages and thereby preventing effectivity of the cholesterol-dependent LLO-mediated phagosomal escape of bacteria.


Assuntos
Listeria monocytogenes/efeitos dos fármacos , Fagossomos/efeitos dos fármacos , Sinvastatina/farmacologia , Animais , Toxinas Bacterianas/metabolismo , Linhagem Celular , Colesterol/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas Hemolisinas/metabolismo , Subunidade p40 da Interleucina-12/metabolismo , Listeria monocytogenes/metabolismo , Listeriose/tratamento farmacológico , Listeriose/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/microbiologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/efeitos dos fármacos , Fagossomos/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/microbiologia , Fator de Necrose Tumoral alfa/metabolismo
18.
Lancet ; 381(9860): 40-6, 2013 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-23122768

RESUMO

BACKGROUND: Patients with homozygous familial hypercholesterolaemia respond inadequately to existing drugs. We aimed to assess the efficacy and safety of the microsomal triglyceride transfer protein inhibitor lomitapide in adults with this disease. METHODS: We did a single-arm, open-label, phase 3 study of lomitapide for treatment of patients with homozygous familial hypercholesterolemia. Current lipid lowering therapy was maintained from 6 weeks before baseline through to at least week 26. Lomitapide dose was escalated on the basis of safety and tolerability from 5 mg to a maximum of 60 mg a day. The primary endpoint was mean percent change in levels of LDL cholesterol from baseline to week 26, after which patients remained on lomitapide through to week 78 for safety assessment. Percent change from baseline to week 26 was assessed with a mixed linear model. FINDINGS: 29 men and women with homozygous familial hypercholesterolaemia, aged 18 years or older, were recruited from 11 centres in four countries (USA, Canada, South Africa, and Italy). 23 of 29 enrolled patients completed both the efficacy phase (26 weeks) and the full study (78 weeks). The median dose of lomitapide was 40 mg a day. LDL cholesterol was reduced by 50% (95% CI -62 to -39) from baseline (mean 8·7 mmol/L [SD 2·9]) to week 26 (4·3 mmol/L [2·5]; p<0·0001). Levels of LDL cholesterol were lower than 2·6 mmol/L in eight patients at 26 weeks. Concentrations of LDL cholesterol remained reduced by 44% (95% CI -57 to -31; p<0·0001) at week 56 and 38% (-52 to -24; p<0·0001) at week 78. Gastrointestinal symptoms were the most common adverse event. Four patients had aminotransaminase levels of more than five times the upper limit of normal, which resolved after dose reduction or temporary interruption of lomitapide. No patient permanently discontinued treatment because of liver abnormalities. INTERPRETATION: Our study suggests that treatment with lomitapide could be a valuable drug in the management of homozygous familial hypercholesterolaemia. FUNDING: FDA Office of the Orphan Product Development, Aegerion Pharmaceuticals.


Assuntos
Benzimidazóis/uso terapêutico , Proteínas de Transporte/antagonistas & inibidores , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Benzimidazóis/efeitos adversos , LDL-Colesterol/sangue , Feminino , Homozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Masculino
19.
Circulation ; 124(20): 2202-7, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21986285

RESUMO

BACKGROUND: Homozygous familial hypercholesterolemia is an inherited disorder caused by mutations in both low-density lipoprotein receptor alleles, which results in extremely elevated plasma low-density lipoprotein cholesterol concentrations and very early morbidity and mortality due to cardiovascular disease. METHODS AND RESULTS: To evaluate the impact of advances in lipid-lowering (predominantly statin) therapy on cardiovascular disease morbidity and mortality in a large cohort of patients with homozygous familial hypercholesterolemia, the records of 149 patients (81 females, 68 males) from 2 specialized lipid clinics in South Africa were evaluated retrospectively. Homozygous familial hypercholesterolemia was diagnosed by confirmation of mutations in genes affecting low-density lipoprotein cholesterol or by clinical criteria. A Cox proportional hazard model with time-varying exposure was used to estimate the risk of death and major adverse cardiovascular events among statin-treated patients compared with statin-naive patients. The hazard ratio for benefit from lipid therapy, calculated with the Cox proportional hazards model for the end point of death, was 0.34 (95% confidence interval 0.14-0.86; P=0.02), and for the end point of major adverse cardiovascular events, it was 0.49 (95% confidence interval 0.22-1.07; P=0.07). This occurred despite a mean reduction in low-density lipoprotein cholesterol of only 26.4% (from 15.9±3.9 to 11.7±3.4 mmol/L; P<0.0001) with lipid-lowering therapy. CONCLUSIONS: Lipid-lowering therapy is associated with delayed cardiovascular events and prolonged survival in patients with homozygous familial hypercholesterolemia.


Assuntos
LDL-Colesterol/genética , Homozigoto , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/mortalidade , Adolescente , Adulto , Criança , LDL-Colesterol/sangue , Estudos de Coortes , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
20.
Circ Cardiovasc Imaging ; 3(4): 398-404, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20494942

RESUMO

BACKGROUND: Until recently, patients with heterozygous familial hypercholesterolemia (HeFH) were considered the best subjects for the assessment of changes in carotid intima-media thickness (cIMT) in randomized intervention trials. Our aims were to investigate whether contemporary statin-treated HeFH patients still show accelerated cIMT increase and to assess the impact of statin treatment, before and after random assignment, on atherosclerosis progression. METHODS AND RESULTS: We retrospectively evaluated cIMT change, and prior statin treatment and postbaseline LDL-C change as predictors of cIMT change, in 1513 HeFH patients who were randomly assigned to the statin arms of the early ASAP and more recent RADIANCE 1, CAPTIVATE, and ENHANCE studies. In the 3 recent studies combined, mean cIMT increased at only 33%of the rate of the simvastatin-treated patients in the ASAP study (0.014 mm/2 years [95% confidence interval, -0.0003-0.028] versus 0.041 mm/2 years [95% confidence interval, 0.020-0.061]; P<0.05). Patients whose statin therapy could be intensified, as evidenced by an LDL-C decrease after the initiation of on-trial statin therapy, showed cIMT decrease in the first 6 to 12 months and a much lower cIMT increase measured over the full 2 years. In line with this, previously statin-naive HeFH patients showed a lower overall cIMT increase. CONCLUSIONS: Over the years, intensification of statin therapy in HeFH patients has resulted in an impressive decrease in carotid atherosclerosis progression. In studies that assess other antiatherosclerotic modalities, statin therapy may still induce rapid changes in cIMT. For future cIMT studies, our analyses suggest that patient populations other than intensively pretreated HeFH patients should be selected and that the statin regimen should not be changed on study initiation.


Assuntos
Doenças das Artérias Carótidas/tratamento farmacológico , Doenças das Artérias Carótidas/patologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/patologia , Progressão da Doença , Determinação de Ponto Final , Feminino , Humanos , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Método de Monte Carlo , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento , Túnica Íntima/patologia , Túnica Média/patologia
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