RESUMO
Sitosterolemia is an autosomal recessive and very rare disease. Its main characteristic is that there is a greater absorption and a decrease in the excretion of sterols, which leads to them being deposited in tissues. It is given by mutations in the ABCG5 or ABCG8 genes found on chromosome 2p21. In this clinical note, we describe the first two patients with familial sitosterolemia described in Colombia, brothers, one of them with xanthomas in extremities as the only symptom, and the other, completely asymptomatic. Genetic studies were performed as a diagnostic test in both patients, where a pathogenic homozygous variant could be identified in the ABCG8 gene in the first case (symptomatic), and a heterozygous variant in the ABCG8 gene in the second case (asymptomatic); the first patient has responded to treatment with ezetimibe. In conclusion, xanthomas should be studied in depth in pediatric age as they may be the only visible sign of such complex and hereditary diseases as familial sitosterolemia, which can be controlled and prevent cardiovascular complications of the disease.
Assuntos
Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Ezetimiba , Hipercolesterolemia , Enteropatias , Erros Inatos do Metabolismo Lipídico , Fitosteróis , Humanos , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/diagnóstico , Masculino , Colômbia , Fitosteróis/efeitos adversos , Fitosteróis/genética , Enteropatias/genética , Enteropatias/diagnóstico , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Hipercolesterolemia/genética , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/diagnóstico , Ezetimiba/uso terapêutico , Xantomatose/genética , Xantomatose/patologia , Xantomatose/diagnóstico , Anticolesterolemiantes/uso terapêutico , Anticolesterolemiantes/administração & dosagem , Mutação , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Homozigoto , Criança , Heterozigoto , Lipoproteínas/genéticaRESUMO
PURPOSE OF REVIEW: The purpose of this review was to summarize important and updated information on sitosterolemia. Sitosterolemia is an inherited lipid disorder consisting of high levels of plasma plant sterols. This sterol storage condition is caused by biallelic loss-of-function genetic variants in either ABCG5 or ABCG8, leading to increased intestinal absorption and decreased hepatic excretion of plant sterols. Clinically, patients with sitosterolemia usually exhibit xanthomatosis, high levels of plasma cholesterol, and premature atherosclerotic disease, but presentation can be highly heterogeneous. Therefore, recognition of this condition requires a high level of suspicion, with confirmation upon genetic diagnosis or through measurement of plasma phytosterols. Treatment of sitosterolemia with both a plant sterol-restricted diet and the intestinal cholesterol absorption inhibitor ezetimibe can reduce efficiently the levels of plasma plant sterols, consisting in the first-line therapy for this disease. RECENT FINDINGS: Since hypercholesterolemia is often present in individuals with sitosterolemia, it is important to search for genetic variants in ABCG5 and ABCG8 in patients with clinical criteria for familial hypercholesterolemia (FH), but no variants in FH implicated genes. Indeed, recent studies have suggested that genetic variants in ABCG5/ABCG8 can mimic FH, and even when in heterozygosis, they may potentially exacerbate the phenotype of patients with severe dyslipidemia. Sitosterolemia is a genetic lipid disorder characterized by increased circulating levels of plant sterols and clinically manifested by xanthomatosis, hematologic disorders, and early atherosclerosis. Awareness about this condition, a rare, but commonly underdiagnosed and yet treatable cause of premature atherosclerotic disease, is imperative.
Assuntos
Aterosclerose , Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Enteropatias , Erros Inatos do Metabolismo Lipídico , Fitosteróis , Xantomatose , Humanos , Hipercolesterolemia/tratamento farmacológico , Fitosteróis/efeitos adversos , Fitosteróis/genética , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/terapia , Enteropatias/diagnóstico , Enteropatias/genética , Enteropatias/tratamento farmacológico , Hiperlipoproteinemia Tipo II/complicações , Colesterol , Xantomatose/etiologia , Aterosclerose/genética , Aterosclerose/complicaçõesRESUMO
This study proposed to determine global microRNA (miRNA) expression and miRNA-regulated pathways in Intestinal Neuronal Dysplasia type B (IND-B). Fifty patients (0-15 years old) with IND-B were included in the study. Peripheral blood samples were collected from all 50 patients and from 10 healthy asymptomatic children (controls). Rectal biopsies were collected from 29/50 patients; biopsy tissues were needle microdissected to isolate the different intestinal layers, for molecular analysis. Global miRNA expression was determined using TaqMan arrays. Correlation analysis between miRNA expression in plasma and biopsy samples as well as among tissues derived from the distinct intestinal layers was performed. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated genes and enriched pathways biologically relevant to IND-B pathogenesis. miRNAs were statistically significantly deregulated (FC ≥ 2 and p ≤ 0.05) in submucosal and muscular layers: over-expressed (miR-146a and miR-146b) and under-expressed (miR-99a, miR-100, miR-130a, miR-133b, miR-145, miR-365, miR-374-5p, miR-451). Notably, let-7a-5p was highly over-expressed in patient plasma compared to healthy controls (FC = 17.4). In addition, miR-451 was significantly under-expressed in both plasma and all biopsy tissues from the same patients. Enriched pathways (p < 0.01) were axon guidance, nerve growth factor signalling, NCAM signalling for neurite out-growth, neuronal system and apoptosis. miRNA expression is deregulated in the submucosa and muscular layers of the rectum and detected in plasma from patients with IND-B. Biologically enriched pathways regulated by the identified miRNAs may play a role in IND-B disease pathogenesis, due to the activity related to the neurons of the enteric nervous system.
Assuntos
Biologia Computacional/métodos , Enteropatias/genética , Enteropatias/patologia , MicroRNAs/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Transcriptoma , Adolescente , Apoptose , Orientação de Axônios , Biópsia , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Recém-Nascido , Enteropatias/sangue , Masculino , Fatores de Crescimento Neural/metabolismo , Doenças do Sistema Nervoso/sangue , Moléculas de Adesão de Célula Nervosa/metabolismo , Reto/patologiaRESUMO
Nearly 70% of cystic fibrosis (CF) patients bear the phenylalanine-508 deletion but disease severity differs greatly, and is not explained by the existence of different mutations in compound heterozygous. Studies demonstrated that genes other than CFTR relate to intestinal disease in humans and CF-mouse. Kcnn4, the gene encoding the calcium-activated potassium channel KCa3.1, important for intestinal secretion, is present in a locus linked with occurrence of intestinal CF-disease in mice and humans. We reasoned that it might be a CF-modifier gene and bred a CF-mouse with Kcnn4 silencing, finding that lethality was almost abolished. Silencing of Kcnn4 did not improve intestinal secretory functions, but rather corrected increased circulating TNF-α level and reduced intestinal mast cell increase. Given the importance of mast cells in intestinal disease additional double mutant CF-animals were tested, one lacking mast cells (C-kitW-sh/W-sh) and Stat6-/- to block IgE production. While mast cell depletion had no effect, silencing Stat6 significantly reduced lethality. Our results show that Kcnn4 is an intestinal CF modifier gene partially acting through a STAT6-dependent mechanism.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Genes Modificadores , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Enteropatias/genética , Animais , Citocinas/metabolismo , Imunoglobulina E/metabolismo , Mediadores da Inflamação/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/deficiência , Mucosa Intestinal/patologia , Ativação do Canal Iônico , Mastócitos/metabolismo , Camundongos Endogâmicos C57BL , Mutação/genética , Fenótipo , Fator de Transcrição STAT6/metabolismo , Análise de Sobrevida , Aumento de PesoRESUMO
Sitosterolemia is an autosomal recessive metabolic disease caused by mutations in ABCG5 or ABCG8 genes which encode for the (ATP)-binding cassette (ABC) transporters that are responsible for the trafficking of xenosterols. Liver involvement is not a recognized manifestation of this disease, and cirrhosis has been reported only once in the medical literature. We describe a fatal case of a 21-year old South Asian male who presented with decompensated cirrhosis, and biochemical abnormalities consistent with sitosterolemia. Genetic testing showed a homozygous pathogenic mutation in ABCG5, confirming the diagnosis. Sitosterolemia is a rare, but likely under-recognized condition, and a high degree of suspicion is imperative to make the diagnosis. We propose that sitosterolemia should be included in the differential diagnosis for patients with cryptogenic cirrhosis, especially as there are effective oral therapies to treat this condition. Newly diagnosed sitosterolemia patients should undergo a thorough hepatology evaluation and follow-up to evaluate for the presence, development, and progression of any hepatic involvement.
Assuntos
Hipercolesterolemia/complicações , Enteropatias/complicações , Erros Inatos do Metabolismo Lipídico/complicações , Cirrose Hepática/etiologia , Fitosteróis/efeitos adversos , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Anemia Hemolítica/etiologia , Anticolesterolemiantes/uso terapêutico , Biópsia , Angiografia Coronária , Doença da Artéria Coronariana/etiologia , Análise Mutacional de DNA , Dieta com Restrição de Gorduras , Ezetimiba/uso terapêutico , Evolução Fatal , Predisposição Genética para Doença , Hereditariedade , Homozigoto , Humanos , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/genética , Hipercolesterolemia/terapia , Enteropatias/diagnóstico , Enteropatias/genética , Enteropatias/terapia , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/terapia , Lipoproteínas/genética , Cirrose Hepática/diagnóstico , Masculino , Microscopia Eletrônica , Mutação , Linhagem , Fenótipo , Fitosteróis/genética , Fatores de Risco , Resultado do Tratamento , Xantomatose/etiologia , Adulto JovemRESUMO
STUDY QUESTION: Is mRNA expression of LDL receptors altered in deep bowel endometriotic foci? SUMMARY ANSWER: mRNA expression of LDL receptors is up-regulated in deep bowel endometriotic foci of patients with endometriosis. WHAT IS KNOWN ALREADY: Several studies have demonstrated the overexpression of low-density lipoprotein receptors in various tumour cell lines and endometriosis has similar aspects to cancer, mainly concerning the pathogenesis of both diseases. This is the first study we know of to investigate lipoprotein receptors expression in deep endometriosis with bowel involvement. STUDY DESIGN, SIZE, DURATION: During 2014-2015, an exploratory case-control study was conducted with 39 patients, including 20 women with a histological diagnosis of deep endometriosis compromising the bowel and 19 women without endometriosis who underwent laparoscopic tubal ligation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Peripheral blood samples were collected on the day of surgery for lipid profile analysis, and samples of endometrial tissue and of bowel endometriotic lesions were also collected. The tissue samples were sent for histopathological analysis and for LDL-R and LRP-1 gene expression screening using quantitative real-time PCR. MAIN RESULTS AND THE ROLE OF CHANCE: Patients with deep endometriosis had lower LDL-cholesterol than patients without the disease (119 ± 23 versus 156 ± 35; P = 0.001). Gene expression analysis of LDL receptors revealed that LDL-R was more highly expressed in endometriotic lesions when compared to the endometrium of the same patient but not more than in the endometrium of women without endometriosis (0.027 ± 0.022 versus 0.012 ± 0.009 versus 0.019 ± 0.01, respectively; P < 0.001). LRP-1 was more highly expressed in endometriotic lesions, both when compared with the endometrium of the same patient and when compared with the endometrium of patients without the disease (0.307 ± 0.207 versus 0.089 ± 0.076 and versus 0.126 ± 0.072, respectively; P < 0.001). The study also showed that LDL-R gene expression in the endometrium of women with endometriosis was higher during the secretory phase of the menstrual cycle (P = 0.001). LRP-1 gene expression was increased during the secretory phase in the endometrium of women without the disease (P = 0.008). LIMITATIONS, REASONS FOR CAUTION: In the endometriotic lesions, the presence of fibrosis is substantial, restricting access to the stromal and glandular components of the lesion. Despite that, we found that LDL receptor mRNA was overexpressed. Future studies may perform laser microdissection to isolate the area of interest in the target tissue, excluding fibrosis contamination. WIDER IMPLICATIONS OF THE FINDINGS: This study supports the feasibility of LDL-R targeted therapy in the treatment of deep endometriosis. STUDY FUNDING/COMPETING INTERESTS: This study was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP #2011/17245-0). The authors have no conflicts of interest to declare.
Assuntos
Endometriose/metabolismo , Enteropatias/metabolismo , Mucosa Intestinal/metabolismo , Receptores de LDL/metabolismo , Adulto , Estudos de Casos e Controles , Endometriose/genética , Endometriose/patologia , Feminino , Humanos , Enteropatias/genética , Enteropatias/patologia , Intestinos/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de LDL/genética , Regulação para CimaRESUMO
Sitosterolemia is a disease characterized by an intestinal hyperabsorption of plant sterols and cholesterol. Affected individuals have mutations in both alleles of either ABCG5 or ABCG8 genes, leading to a total loss of one of the proteins and subsequent functional deficiency. We here report a Mexican family with clinical and biochemical features of sitosterolemia carrying 2 new mutations of the ABCG5 gene. Concentrations of sitosterol, campesterol, and cholesterol were found to be higher for the index case (a 10-year-old girl) than for her also affected sibling (64.1 vs 19 mg/dL, 32 vs 12.1 mg/dL, and cholesterol 295 vs 235 mg/dL, respectively). Both individuals showed 2 new ABCG5 gene mutations identified by sequencing, which is concordant with their biochemical diagnosis of sitosterolemia. The first mutation was a c.144 -1G>A transition that disrupts the intron 1 splicing acceptor site. The second mutation is the deletion c.1523 delC, which occurred in exon 11, causing an amino acid change at codon 510 (p.His510Thr) and a stop codon at codon 511 (p.Leu511X). The father is heterozygote for the mutation c.144 -1G>A, whereas the mother is heterozygote for the mutation c.1523 delC. In conclusion, we here report the first case of a Mexican family with sitosterolemia carrying two new ABCG5 gene mutations.
Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Hipercolesterolemia/genética , Enteropatias/genética , Erros Inatos do Metabolismo Lipídico/genética , Lipoproteínas/genética , Mutação , Linhagem , Fitosteróis/efeitos adversos , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Adolescente , Sequência de Bases , Criança , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fitosteróis/genética , Adulto JovemRESUMO
Intestinal mucositis is a common side effect of irinotecan-based anticancer regimens. Mucositis causes cell damage, bacterial/endotoxin translocation and production of cytokines including IL-1 and IL-18. These molecules and toll-like receptors (TLRs) activate a common signaling pathway that involves the Myeloid Differentiation adaptor protein, MyD88, whose role in intestinal mucositis is unknown. Then, we evaluated the involvement of TLRs and MyD88 in the pathogenesis of irinotecan-induced intestinal mucositis. MyD88-, TLR2- or TLR9-knockout mice and C57BL/6 (WT) mice were given either saline or irinotecan (75 mg/kg, i.p. for 4 days). On day 7, animal survival, diarrhea and bacteremia were assessed, and following euthanasia, samples of the ileum were obtained for morphometric analysis, myeloperoxidase (MPO) assay and measurement of pro-inflammatory markers. Irinotecan reduced the animal survival (50%) and induced a pronounced diarrhea, increased bacteremia, neutrophil accumulation in the intestinal tissue, intestinal damage and more than twofold increased expression of MyD88 (200%), TLR9 (400%), TRAF6 (236%), IL-1ß (405%), IL-18 (365%), COX-2 (2,777%) and NF-κB (245%) in the WT animals when compared with saline-injected group (P<0.05). Genetic deletion of MyD88, TLR2 or TLR9 effectively controlled the signs of intestinal injury when compared with irinotecan-administered WT controls (P<0.05). In contrast to the MyD88-/- and TLR2-/- mice, the irinotecan-injected TLR9-/- mice showed a reduced survival, a marked diarrhea and an enhanced expression of IL-18 versus irinotecan-injected WT controls. Additionally, the expression of MyD88 was reduced in the TLR2-/- or TLR9-/- mice. This study shows a critical role of the MyD88-mediated TLR2 and TLR9 signaling in the pathogenesis of irinotecan-induced intestinal mucositis.
Assuntos
Bacteriemia/metabolismo , Diarreia/metabolismo , Enteropatias/metabolismo , Mucosite/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais/fisiologia , Animais , Bacteriemia/induzido quimicamente , Bacteriemia/genética , Camptotecina/análogos & derivados , Diarreia/induzido quimicamente , Diarreia/genética , Enteropatias/induzido quimicamente , Enteropatias/genética , Mucosa Intestinal/metabolismo , Irinotecano , Camundongos , Camundongos Knockout , Mucosite/induzido quimicamente , Mucosite/genética , Fator 88 de Diferenciação Mieloide/genética , Peroxidase/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismoRESUMO
Cytokines are small cell-signaling proteins that play an important role in the immune system, participating in intracellular communication. Four candidate genes of the cytokine family (IL2, IL4, IL13, and IFNG) were selected to identify Single Nucleotide Polymorphisms (SNPs) that might be associated with resistance to gastrointestinal endoparasites in goats. A population of 229 goats, F2 offspring from an F1 intercross was produced by crossing pure Saanen goats, considered as susceptible to gastrointestinal endoparasites, with pure Anglo-Nubian goats, considered resistant. Blood was collected for DNA extraction and fecal samples were also collected for parasite egg count. Polymorphisms were prospected by sequencing animals with extreme phenotype for fecal egg count (FEC) distribution. The association between SNPs and phenotype was determined by using the Fisher exact test with correction for multiple tests. Three of the 10 SNPs were identified as significant (P ≤ 0.03). They were found in intron 1 of IL2 (ENSBTA00000020883), intron 3 of IL13 (ENSBTA00000015953) and exon 3 of IFNG (ENSBTA00000012529), suggesting an association between them and gastrointestinal endoparasite resistance. Further studies will help describe the effects of these markers accurately before implementing them in marker assisted selection. This study is the pioneer in describing such associations in goats.
Assuntos
Enteropatias/genética , Infecções por Nematoides/genética , Polimorfismo de Nucleotídeo Único , Alelos , Animais , Citocinas/genética , Loci Gênicos , Genótipo , Cabras , Enteropatias/parasitologia , Infecções por Nematoides/parasitologiaRESUMO
Tufting enteropathy (TE), also known as intestinal epithelial dysplasia (IED), is a rare congenital enteropathy related to an earlyonset of severe intractable diarrhea due to specific abnormalities of the intestinal epithelium and mutations of the EpCAM gene. TE is characterized by clinical and histological heterogeneity, such as with low or without mononuclear cell infiltration of the lamina propria, and abnormalities of basement membrane. TE can be associated with malformations, other epithelial diseases, or to abnormal enterocytes development and/or differentiation. The authors report a case of a Brazilian child with TE associated with c.556-14A>G mutation in the EpCAM gene (NM_002354.2)...
Enteropatia com formação de tufos epiteliais (ETE), também conhecida como displasia epitelial intestinal (DEI), é uma rara enteropatia congênita relacionada com um início precoce de diarreia intratável grave devido a anormalidades específicas do epitélio intestinal e mutações do gene EpCAM. ETE caracteriza-se por uma heterogeneidade clínica e histológica, como ausência ou leve infiltrado de células mononucleares na lâmina própria e anormalidades de membrana basal. Pode ser associada a malformações, outras doenças epiteliais ou anormalidades no desenvolvimento/na diferenciação dos enterócitos. Os autores relatam um caso de ETE, em uma criança brasileira, associada à mutação c.556-14A> g do gene EPCAM (NM_002354.2)...