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1.
Gastroenterology ; 158(6): 1597-1610.e7, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31987796

RESUMEN

BACKGROUND & AIMS: Dysbiosis of the intestinal microbiota has been associated with nonalcoholic fatty liver disease (NAFLD). We investigated whether administration of a synbiotic combination of probiotic and prebiotic agents affected liver fat content, biomarkers of liver fibrosis, and the composition of the fecal microbiome in patients with NAFLD. METHODS: We performed a double-blind phase 2 trial of 104 patients with NAFLD in the United Kingdom. Participants (mean age, 50.8 ± 12.6 years; 65% men; 37% with diabetes) were randomly assigned to groups given the synbiotic agents (fructo-oligosaccharides, 4 g twice per day, plus Bifidobacterium animalis subspecies lactis BB-12; n = 55) or placebo (n = 49) for 10-14 months. Liver fat content was measured at the start and end of the study by magnetic resonance spectroscopy, and liver fibrosis was determined from a validated biomarker scoring system and vibration-controlled transient elastography. Fecal samples were collected at the start and end of the study, the fecal microbiome were analyzed by 16S ribosomal DNA sequencing. RESULTS: Mean baseline and end-of-study magnetic resonance spectroscopy liver fat percentage values were 32.3% ± 24.8% and 28.5% ± 20.1% in the synbiotic group and 31.3% ± 22% and 25.2% ± 17.2% in the placebo group. In the unadjusted intention-to-treat analysis, we found no significant difference in liver fat reduction between groups (ß = 2.8; 95% confidence interval, -2.2 to 7.8; P = .30). In a fully adjusted regression model (adjusted for baseline measurement of the outcome plus age, sex, weight difference, and baseline weight), only weight loss was associated with a significant decrease in liver fat (ß = 2; 95% confidence interval, 1.5-2.6; P = .03). Fecal samples from patients who received the synbiotic had higher proportions of Bifidobacterium and Faecalibacterium species, and reductions in Oscillibacter and Alistipes species, compared with baseline; these changes were not observed in the placebo group. Changes in the composition of fecal microbiota were not associated with liver fat or markers of fibrosis. CONCLUSIONS: In a randomized trial of patients with NAFLD, 1 year of administration of a synbiotic combination (probiotic and prebiotic) altered the fecal microbiome but did not reduce liver fat content or markers of liver fibrosis. (ClinicalTrials.gov, Number: NCT01680640).


Asunto(s)
Disbiosis/dietoterapia , Microbioma Gastrointestinal/efectos de los fármacos , Hígado/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Simbióticos/administración & dosificación , Adulto , Bifidobacterium animalis , Biomarcadores/análisis , Biopsia , Método Doble Ciego , Disbiosis/complicaciones , Diagnóstico por Imagen de Elasticidad , Heces/microbiología , Femenino , Humanos , Lípidos/análisis , Hígado/química , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/prevención & control , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/microbiología , Enfermedad del Hígado Graso no Alcohólico/patología , Oligosacáridos/administración & dosificación , Prueba de Estudio Conceptual , Reino Unido
2.
J Hepatol ; 72(3): 411-419, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31655133

RESUMEN

BACKGROUND & AIM: Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in adults and children. Along with obesity, diabetes and insulin resistance, genetic factors strongly impact on NAFLD development and progression. Dysregulated bile acid metabolism and the fibroblast growth factor 19 (FGF19) pathway play a pivotal role in NAFLD pathogenesis. However, the mechanism through which the FGF19 receptor system is associated with liver damage in NAFLD remains to be defined. METHODS: We evaluated the impact of the rs17618244 G>A ß-Klotho (KLB) variant on liver damage in 249 pediatric patients with biopsy-proven NAFLD and the association of this variant with the expression of hepatic and soluble KLB. In vitro models were established to investigate the role of the KLB mutant. RESULTS: The KLB rs17618244 variant was associated with an increased risk of ballooning and lobular inflammation. KLB plasma levels were lower in carriers of the rs17618244 minor A allele and were associated with lobular inflammation, ballooning and fibrosis. In HepG2 and Huh7 hepatoma cell lines, exposure to free fatty acids caused a severe reduction of intracellular and secreted KLB. Finally, KLB downregulation obtained by the expression of a KLB mutant in HepG2 and Huh7 cells induced intracellular lipid accumulation and upregulation of p62, ACOX1, ACSL1, IL-1ß and TNF-α gene expression. CONCLUSION: In conclusion, we showed an association between the rs17618244 KLB variant, which leads to reduced KLB expression, and the severity of NAFLD in pediatric patients. We can speculate that the KLB protein may exert a protective role against lipotoxicity and inflammation in hepatocytes. LAY SUMMARY: Genetic and environmental factors strongly impact on the pathogenesis and progression of non-alcoholic fatty liver disease (NAFLD). The FGF19/FGFR4/KLB pathway plays a pivotal role in the pathogenesis of NAFLD. The aim of the study was to investigate the impact of a genetic variant in the KLB gene on the severity of liver disease. Our data suggest that the KLB protein plays a protective role against lipotoxicity and inflammation in hepatocytes.


Asunto(s)
Cirrosis Hepática/sangre , Cirrosis Hepática/genética , Proteínas de la Membrana/sangre , Proteínas de la Membrana/genética , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/genética , Polimorfismo de Nucleótido Simple , Adolescente , Alelos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Estudios de Casos y Controles , Niño , Regulación hacia Abajo/genética , Femenino , Factores de Crecimiento de Fibroblastos/metabolismo , Células Hep G2 , Humanos , Inflamación/sangre , Inflamación/epidemiología , Proteínas Klotho , Hígado/patología , Cirrosis Hepática/epidemiología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/patología , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/metabolismo , Ciudad de Roma/epidemiología
3.
J Pediatr ; 216: 117-127.e2, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31526528

RESUMEN

OBJECTIVE: To evaluate the histopathologic modifications in liver and visceral adipose tissue (VAT), and to correlate these changes with clinical measures, adipokine production, and proinflammatory cytokines in a population of adolescents with obesity with nonalcoholic fatty liver disease (NAFLD) who underwent laparoscopic sleeve gastrectomy (LSG). STUDY DESIGN: Twenty adolescents with obesity who underwent LSG and with biopsy-proven NAFLD were included. Patients underwent clinical evaluation and blood tests at baseline and 1 year after the surgical procedure. Liver and VAT specimens were processed for routine histology, immunohistochemistry, and immunofluorescence. RESULTS: In adolescents with obesity and NAFLD, hepatic histologic alterations were uncorrelated with VAT inflammation. LSG induced in both liver and VAT tissue histopathology amelioration and macrophage profile modification that were correlated with body mass index and improvement in insulin resistance. The adipokine profile in liver and VAT was associated with weight loss and histologic improvement after LSG. Serum proinflammatory cytokines were correlated with liver and VAT histopathology and IL-1ß and IL-6 levels were independently predicted by liver necroinflammatory grade. CONCLUSIONS: This study suggests a unique adipose tissue/fatty liver crosstalk in pediatric patients. LSG induces a similar pattern of histologic improvement in the liver and in VAT. Besides VAT, our results strengthen the role of the liver in adipocytokine production and its contribution to systemic inflammation in pediatric patients with NAFLD.


Asunto(s)
Gastrectomía/métodos , Grasa Intraabdominal/patología , Laparoscopía , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad Infantil/cirugía , Adipoquinas/biosíntesis , Adolescente , Correlación de Datos , Femenino , Humanos , Grasa Intraabdominal/metabolismo , Hígado/metabolismo , Macrófagos , Masculino , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Obesidad Infantil/complicaciones , Estudios Prospectivos
4.
Hepatology ; 70(1): 142-153, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30912854

RESUMEN

Emerging evidence suggests that patatin-like phospholipase domain-containing protein-3 (PNPLA3) rs738409 genotype (the major genetic variant associated with susceptibility to nonalcoholic fatty liver disease [NAFLD]) is associated with decreased kidney function in adults. Currently, it is uncertain whether this association also occurs in children/adolescents and whether any association is independent of liver disease severity. We enrolled a sample of 142 Caucasian children and adolescents with biopsy-proven NAFLD, presenting to the Liver Unit of the "Bambino Gesù" Children's Hospital. The glomerular filtration rate (e-GFR) was estimated using the Bedside Schwartz equation, whereas 24-hour proteinuria was measured using a radioimmunoassay method. Genotyping for the PNPLA3 rs738409 genotype was undertaken using the single-nucleotide polymorphism genotyping allelic discrimination method. Overall, 45 children had G/G, 56 had G/C, and 41 had C/C PNPLA3 rs738409 genotype, respectively. Children with G/G genotype had significantly lower e-GFR (107.5 ± 20 versus 112.8 ± 18 versus 125.3 ± 23 mL/min/1.73 m2 , P = 0.002) and higher 24-hour proteinuria (58.5 ± 21 versus 53.9 ± 22 versus 42.9 ± 20 mg/day, P = 0.012) compared with those with either G/C or C/C genotypes. After adjustment for age, sex, systolic blood pressure, measures of adiposity, homeostasis model assessment-estimated insulin resistance and biopsy-confirmed nonalcoholic steatohepatitis and stage of liver fibrosis, the presence of rs738409 G/G genotype was independently associated with both lower e-GFR (ß coefficient: -23.6; 95% confidence interval [CI]: -36.3 to -10.8; P < 0.001) and higher 24-hour proteinuria (ß coefficient: 15.3; 95% CI: 1.12 to 30.5; P = 0.046). Conclusion: Regardless of established renal risk factors and the histological severity of NAFLD, the PNPLA3 G/G genotype was strongly associated with decreasing kidney function and increasing 24-hour proteinuria in children/adolescents with histologically confirmed NAFLD.


Asunto(s)
Riñón/fisiopatología , Lipasa/genética , Proteínas de la Membrana/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Proteinuria/genética , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Enfermedad del Hígado Graso no Alcohólico/orina
5.
Hepatology ; 70(3): 812-823, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30706504

RESUMEN

Recent cross-sectional studies have examined the association between nonalcoholic fatty liver disease (NAFLD) and bone mineral density (BMD) in children or adolescents, but these have produced conflicting results. We performed a systematic review and meta-analysis of these published studies to quantify the magnitude of the association, if any, between NAFLD and BMD. We searched publication databases from January 2000 to September 2018, using predefined keywords to identify relevant observational studies conducted in children or adolescents in whom NAFLD was diagnosed either by imaging or by histology and BMD Z score was measured by dual-energy X-ray absorptiometry. Data from selected studies were extracted, and a meta-analysis was performed using random-effects modeling. A total of eight observational cross-sectional or case-control studies enrolling 632 children and adolescents (mean age 12.8 years), 357 of whom had NAFLD, were included in the final analysis. Meta-analysis showed significant differences in whole-body or lumbar BMD Z scores between children/adolescents with and without NAFLD (n = 6 studies; pooled weighted mean difference [WMD], -0.48; 95% confidence interval [CI], -0.74 to -0.21; I2 = 55.5%), as well as between those with biopsy-confirmed nonalcoholic steatohepatitis (NASH) and those with no-NASH (n = 4 studies; pooled WMD, -0.27; 95% CI, -0.40 to -0.13; I2 = 0%). The aforementioned WMDs in BMD Z scores were independent of common clinical risk factors, such as age, sex, race/ethnicity, and body mass index. Sensitivity analyses did not modify these findings. Funnel plot and Egger test did not reveal significant publication bias. Conclusion: This meta-analysis shows that the presence and severity of NAFLD are significantly associated with reduced whole-body BMD Z scores in children and adolescents; however, the observational design of the studies included does not allow for proving causality.


Asunto(s)
Absorciometría de Fotón/métodos , Densidad Ósea , Enfermedades Óseas Metabólicas/epidemiología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/patología , Adolescente , Distribución por Edad , Biopsia con Aguja , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Niño , Comorbilidad , Estudios Transversales , Bases de Datos Factuales , Femenino , Humanos , Inmunohistoquímica , Incidencia , Masculino , Prevalencia , Pronóstico , Estudios Retrospectivos , Distribución por Sexo
6.
J Lipid Res ; 60(6): 1144-1153, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30918065

RESUMEN

Dyslipidemia and altered iron metabolism are typical features of nonalcoholic fatty liver disease (NAFLD). Proprotein convertase subtilisin/kexin type 7 (PCSK7) gene variation has been associated with circulating lipids and liver damage during iron overload. The aim of this study was to examine the impact of the PCSK7 rs236918 variant on NAFLD-related traits in 1,801 individuals from the Liver Biopsy Cohort (LBC), 500,000 from the UK Biobank Cohort (UKBBC), and 4,580 from the Dallas Heart Study (DHS). The minor PCSK7 rs236918 C allele was associated with higher triglycerides, aminotransferases, and hepatic inflammation in the LBC (P < 0.05) and with hypercholesterolemia and liver disease in the UKBBC. In the DHS, PCSK7 missense variants were associated with circulating lipids. PCSK7 was expressed in hepatocytes and its hepatic expression correlated with that of lipogenic genes (P < 0.05). The rs236918 C allele was associated with upregulation of a new "intra-PCSK7" long noncoding RNA predicted to interact with the protein, higher hepatic and circulating PCSK7 protein (P < 0.01), which correlated with triglycerides (P = 0.04). In HepG2 cells, PCSK7 deletion reduced lipogenesis, fat accumulation, inflammation, transforming growth factor ß pathway activation, and fibrogenesis. In conclusion, PCSK7 gene variation is associated with dyslipidemia and more severe liver disease in high risk individuals, likely by modulating PCSK7 expression/activity.


Asunto(s)
Dislipidemias/metabolismo , Enfermedades Metabólicas/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Subtilisinas/metabolismo , Adulto , Animales , Estudios Transversales , Dislipidemias/genética , Femenino , Genotipo , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Desequilibrio de Ligamiento/genética , Desequilibrio de Ligamiento/fisiología , Lipogénesis/genética , Lipogénesis/fisiología , Masculino , Enfermedades Metabólicas/genética , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/genética , Subtilisinas/genética
7.
J Hepatol ; 71(4): 802-810, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31279904

RESUMEN

BACKGROUND & AIMS: We undertook a cross-sectional study of children/adolescents with and without non-alcoholic fatty liver disease (NAFLD) to compare the prevalence of prediabetes and diabetes, and to examine the role of abnormal glucose tolerance as a predictor of liver disease severity. METHODS: We recruited a cohort of 599 Caucasian children/adolescents with biopsy-proven NAFLD, and 118 children/adolescents without NAFLD, who were selected to be similar for age, sex, body mass index and waist circumference to those with NAFLD. The diagnosis of prediabetes and diabetes was based on either hemoglobin A1c, fasting plasma glucose or 2 h post-load glucose concentrations. RESULTS: Children/adolescents with NAFLD had a significantly higher prevalence of abnormal glucose tolerance (prediabetes or diabetes) than those without NAFLD (20.6% vs. 11%, p = 0.02). In particular, 124 (20.6%) children/adolescents with NAFLD had abnormal glucose tolerance, with 19.8% (n = 119) satisfying the diagnostic criteria for prediabetes and 0.8% (n = 5) satisfying the criteria for diabetes. The combined presence of prediabetes and diabetes was associated with a nearly 2.2-fold increased risk of non-alcoholic steatohepatitis (NASH; unadjustedodds ratio 2.19; 95% CI 1.47-3.29; p <0.001). However, this association was attenuated (but remained significant) after adjustment for age, sex, waist circumference (adjustedodds ratio 1.69, 95% CI 1.06-2.69, p = 0.032), and the PNPLA3 rs738409 polymorphism. Both this PNPLA3 polymorphism and waist circumference were strongly associated with NASH. CONCLUSIONS: Abnormal glucose tolerance (especially prediabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. These children also have a higher risk of NASH, though central adiposity is the factor that is most strongly associated with NASH. LAY SUMMARY: Children with biopsy-proven non-alcoholic fatty liver disease (NAFLD) have a higher prevalence of abnormal glucose tolerance (prediabetes or type 2 diabetes) than children without NAFLD. Children with biopsy-proven NAFLD and abnormal glucose tolerance also have a higher prevalence of the progressive form of disease, non-alcoholic steatohepatitis, than those with normal glucose tolerance, though central adiposity is the factor that is most strongly associated with non-alcoholic steatohepatitis.


Asunto(s)
Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico , Obesidad Abdominal , Estado Prediabético , Adolescente , Biopsia/métodos , Biopsia/estadística & datos numéricos , Índice de Masa Corporal , Niño , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/diagnóstico , Intolerancia a la Glucosa/epidemiología , Hemoglobina Glucada/análisis , Humanos , Masculino , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad Abdominal/diagnóstico , Obesidad Abdominal/epidemiología , Estado Prediabético/sangre , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología , Prevalencia , Factores de Riesgo
8.
Clin Gastroenterol Hepatol ; 17(8): 1457-1476.e7, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-29857146

RESUMEN

BACKGROUND & AIMS: There are no approved treatments for pediatric nonalcoholic fatty liver disease (NAFLD) and there is a lack of consensus on the best outcome measure for randomized controlled trials. We performed a systematic review of treatments tested for pediatric NAFLD, the degree of heterogeneity in trial design, and endpoints analyzed in these studies. METHODS: We searched publication databases and clinical trial registries through January 7, 2018 for randomized controlled trials (published and underway) of children (<18 years) with NAFLD. We assessed improvements in histologic features, radiologic and biochemical markers of reduced fibrosis, metabolic syndrome parameters, and adverse events. The quality of the trials was assessed using a modified version of the Cochrane risk of bias tool. RESULTS: Our final analysis included 21 randomized controlled trials, comprising 1307 participants (mean age, 12.6 years; 63% male; mean duration of intervention, 8 months). Most studies evaluated weight loss with lifestyle intervention (n=8), oral polyunsaturated fatty acid treatment (PUFAs, n=6), or oral antioxidant treatment (n=7). Biomarkers of NAFLD decreased with weight loss, but most studies did not include histologic data. Trials of antioxidants were heterogeneous; some reported reduced histologic features of steatohepatitis with no effect on triglycerides or insulin resistance. PUFAs and probiotics reduced radiologic markers of steatosis, insulin resistance, and levels of triglycerides. Only 38% of the trials had biopsy-proven NAFLD as an inclusion criterion. There was heterogeneity in trial primary endpoints; 10 studies (48%) used levels of aminotransferases or ultrasonography findings as a primary endpoint and only 3 trials (14%) used histologic features as the primary endpoint. We identified 13 randomized controlled trials that are underway in children with NAFLD. None of the protocols include collection of liver biopsies; 9 trials (69%) will use magnetic resonance imaging quantification of steatosis as a primary outcome. CONCLUSIONS: In a systematic review of published and active randomized controlled trials of children with NAFLD, we found a large amount of heterogeneity in study endpoints and inclusion criteria. Few trials included histologic analyses. Antioxidants appear to reduce some features of steatohepatitis. Effects of treatment with lifestyle modification, PUFAs, or probiotics have not been validated with histologic analysis. Trials that are underway quantify steatosis magnetic resonance imaging-outcomes are anticipated.


Asunto(s)
Dieta , Ácidos Grasos Insaturados/uso terapéutico , Estilo de Vida , Enfermedad del Hígado Graso no Alcohólico/terapia , Pérdida de Peso/fisiología , Niño , Progresión de la Enfermedad , Humanos , Pronóstico
9.
Clin Gastroenterol Hepatol ; 17(11): 2310-2319.e6, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30708111

RESUMEN

BACKGROUND & AIMS: In patients with nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH) is a risk factor for the development of fibrosis. However, fibrosis has been observed in livers of patients without NASH. We aimed to estimate the prevalence of fibrosis in patients without NASH and risk factors for fibrosis. METHODS: We analyzed data from 1738 subjects (44.9% with severe obesity) in a cross-sectional liver biopsy cohort enrolled at referral centers in Italy and Finland. Biopsy specimens were analyzed histologically by a blinded pathologist at each center, and a diagnosis of NASH was made based on steatosis (≥5% of hepatocytes), hepatocellular ballooning, and lobular inflammation. We also collected data on demographic features, metabolic comorbidities, and genetic factors, and performed logistic regression analyses. Findings were validated using data from 118 consecutive patients with NAFLD who underwent sequential liver biopsies at tertiary referral centers in Italy. RESULTS: In the cross-sectional cohort, 132 of 389 patients (33.9%) with significant fibrosis had no NASH and 39 patients (10.0%) had no inflammation. The dissociation between NASH and fibrosis was significantly greater in patients with severe obesity (P < .005). Steatosis, ballooning, and lobular inflammation each were associated independently with significant fibrosis (P < .001); age, adiposity, fasting hyperglycemia, and the PNPLA3 I148M variant also were associated with fibrosis. In patients without, but not in those with NASH, significant fibrosis was associated with steatosis grade and the PNPLA3 I148M variant. In patients without NASH, age, fasting hyperglycemia, ballooning, and inflammation were associated with fibrosis. In the validation cohort, 16 of 47 patients (34.0%) with clinically significant fibrosis did not have NASH at baseline. In patients with fibrosis without baseline NASH, worsening of fibrosis (based on later biopsies) was associated with fasting hyperglycemia and more severe steatosis (P = .016). CONCLUSIONS: In an analysis of biopsy specimens collected from patients with NAFLD at a single time point, one third of patients with significant fibrosis did not have NASH. We validated this finding in a separate cohort. In patients without NASH, fasting hyperglycemia, severe steatosis, mild inflammation or ballooning, and the PNPLA3 I148M variant identified those at risk of significant fibrosis.


Asunto(s)
Cirrosis Hepática/epidemiología , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Medición de Riesgo/métodos , Adulto , Biopsia , Estudios Transversales , Hígado Graso , Femenino , Humanos , Italia/epidemiología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/etiología , Masculino , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Prevalencia , Factores de Riesgo
10.
J Pediatr ; 211: 72-77.e4, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31128886

RESUMEN

OBJECTIVE: To evaluate, in patients with nonalcoholic fatty liver disease (NAFLD), the role of lifetime exposures associated with genetic predisposition, family history (parental obesity, economic income), programming during fetal life (gestational age, birthweight), being breastfed or not, and later biomarkers of dietary habits and lifestyle in the development of fibrosis. STUDY DESIGN: In total, 182 children with overweight/obesity diagnosed with NAFLD proven by biopsy results were enrolled in our study and evaluated for liver fibrosis. We estimated prevalence ORs of fibrosis according to genetics, parental obesity, occupational socioeconomic status (SES), birth weight, breastfeeding, fructose intake (indicator of junk food consumption), and vitamin D status (inflammatory indicator) using logistic regression models, adjusted for age and children's body mass. RESULTS: One hundred thirty-seven patients (75.3%) had liver fibrosis, and 45 patients (24.7%) did not have liver fibrosis. The ORs of fibrosis were significant (P < .05) for patatin like phospholipase domain-containing 3-GG genotype (OR 2.1), parental obesity (OR 2.9), not being breastfed (OR 3.1), vitamin D status (<20 mg/dL) (OR 1.24), and fructose consumption (OR 1.6 per 1 g/day increase), whereas a high SES maternal occupation was inversely associated with fibrosis (OR 0.30). CONCLUSIONS: Our results show independent roles of the patatin like phospholipase domain-containing 3 gene, parental obesity, maternal SES, and postnatal diet and lifestyle in the development of progressive liver disease secondary to NAFLD.


Asunto(s)
Predisposición Genética a la Enfermedad , Enfermedad del Hígado Graso no Alcohólico/genética , Peso al Nacer , Lactancia Materna , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Salud de la Familia , Femenino , Fructosa/metabolismo , Edad Gestacional , Humanos , Inflamación , Estilo de Vida , Lipasa/genética , Hígado/patología , Cirrosis Hepática/patología , Masculino , Proteínas de la Membrana/genética , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad/complicaciones , Polimorfismo Genético , Embarazo , Complicaciones del Embarazo , Efectos Tardíos de la Exposición Prenatal , Clase Social , Vitamina D/sangre
11.
Liver Int ; 39(12): 2317-2329, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31436362

RESUMEN

BACKGROUND & AIMS: We examined the diagnostic performance of plasma N-terminal propeptide of type III procollagen (PIIINP) levels, aspartate aminotransferase to platelet ratio index (APRI) and Fibrosis-4 (FIB-4) score for predicting non-alcoholic steatohepatitis (NASH) and liver fibrosis stage in children/adolescents with non-alcoholic fatty liver disease (NAFLD). METHODS: We enrolled 204 children/adolescents with biopsy-proven NAFLD at the "Bambino Gesù" Children's Hospital. We measured plasma PIIINP levels using a commercially available enzyme-linked immunosorbent assay kit and calculated APRI and FIB-4 scores using standard methods. RESULTS: Children with NASH had higher plasma PIIINP levels, APRI and FIB-4 scores compared with those without NASH (all P < .001). However, PIIINP levels had much better diagnostic performance and accuracy than APRI and FIB-4 scores for predicting liver fibrosis stage. PIIINP levels correlated with the total NAFLD activity score (NAS) and its constituent components (P < .0001). The risk of either NASH or F ≥ 2 fibrosis progressively increased with increasing PIIINP levels (P < .0001), independent of age, gender, adiposity measures, insulin resistance, NAS score and the patatin-like phospholipase domain-containing protein-3 rs738409 polymorphism. For every 3.6 ng/mL increase in PIIINP levels, the likelihood of having F ≥ 2 fibrosis increased by ~14-fold (adjusted-odds ratio 14.1, 95% CI 5.50-35.8, P < .0001) after adjustment for the aforementioned risk factors. The area under the receiver operating characteristics curve was 0.921 (95% CI 0.87-0.97) for F ≥ 2 fibrosis, and 0.993 (95% CI 0.98-1.0) for F3 fibrosis respectively. CONCLUSIONS: Unlike APRI and FIB-4 scores, plasma PIIINP levels are a promising, non-invasive biomarker for diagnosing liver fibrosis stage in children/adolescents with biopsy-proven NAFLD.


Asunto(s)
Cirrosis Hepática/sangre , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/sangre , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Adolescente , Biomarcadores/sangre , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/patología , Índice de Severidad de la Enfermedad
12.
Scand J Gastroenterol ; 54(7): 822-829, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31535579

RESUMEN

Eosinophilic Esophagitis (EoE) is a chronic immune/antigen-mediated condition which is also driven by genetic and environmental factors. It has been deeply investigated over the last years and its incidence is widely increasing in childhood. Although atopic diseases are closely linked with EoE, it does not recognize a classical IgE-mediate immune pathogenesis but it is rather a T helper type 2 inflammatory process. Familial clustering supports genetic predisposition in EoE and recent advances in understanding the genetic basis for EoE may eventually translate into targeted management of the disease. EoE diagnosis is based on clinical symptoms, micro, and macroscopic findings along with exclusion of gastroesophageal reflux disease (GERD) evidence. Management of the disease encompasses both dietary and pharmacological solutions that need to be specifically targeted on patients' history, clinical symptoms, and diagnostic evaluations. New therapies, currently not available in children, may represent the basis for future therapeutic options in the next years.


Asunto(s)
Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/terapia , Esófago/patología , Terapia Biológica , Niño , Diagnóstico Diferencial , Dieta , Dilatación , Endoscopía del Sistema Digestivo , Estenosis Esofágica/etiología , Estenosis Esofágica/terapia , Hipersensibilidad a los Alimentos/fisiopatología , Reflujo Gastroesofágico/fisiopatología , Predisposición Genética a la Enfermedad , Glucocorticoides/uso terapéutico , Humanos , Inhibidores de la Bomba de Protones/uso terapéutico
13.
J Pediatr Gastroenterol Nutr ; 69(2): 212-217, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31058770

RESUMEN

OBJECTIVE: The aim of the study was to evaluate long-term nutritional outcomes and clinical characteristics in a cohort of children with pediatric intestinal pseudo-obstruction (PIPO) at neonatal-onset (NO-PIPO) and at later-onset (LO-PIPO). METHODS: All children fulfilling new PIPO criteria over a 30-year period were reviewed. Baseline demographic and clinical features as well as nutritional outcomes were collected. Nutritional outcomes included overall survival, prevalence of enteral autonomy and parenteral nutrition (PN) dependency, rate of major PN complications, and growth course. RESULTS: Forty-four patients were still alive at the end of the follow-up. Twenty-five patients (57%) achieved enteral autonomy, whilst 18 remained on PN. Among the patients requiring PN at the beginning of the study period, we found that 55% (CI 34-70) has the probability of remaining on PN at the latest follow-up. Prevalence of gastrointestinal obstruction symptoms (P < 0.01), urinary involvement (P < 0.05), stoma placements [gastrostomy (P < 0.01), ileostomy P < 0.05)] and complex gastrointestinal surgery (P < 0.05) were significantly higher in NO-PIPO than in LO-PIPO. The number of patients requiring long-term PN (P < 0.001) and the number of PN days (P < 0.05) were significantly higher in NO-PIPO, whilst the number of patients achieving enteral autonomy was significantly higher in LO-PIPO (P < 0.05). CONCLUSIONS: In our study, we have reported the nutritional outcome of a cohort of children with PIPO over a 30-year period showing that about 20% of patients develop irreversible intestinal failure requiring life-long PN. Nutritional and clinical outcomes seem to be influenced by the time of onset of the disease.


Asunto(s)
Seudoobstrucción Intestinal/terapia , Adolescente , Adulto , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Estudios de Cohortes , Nutrición Enteral , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Seudoobstrucción Intestinal/mortalidad , Italia , Masculino , Registros Médicos , Nutrición Parenteral , Estudios Retrospectivos , Adulto Joven
14.
J Pediatr Gastroenterol Nutr ; 68(5): 700-705, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30676519

RESUMEN

OBJECTIVES: We aimed to investigate national allocation policies for pediatric liver transplantation (LT). METHOD: A survey was prepared by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Hepatology Committee in collaboration with the North American Studies of Pediatric Liver Transplantation consortium. The survey was sent to pediatric hepatologists and transplant surgeons worldwide. National data were obtained from centrally based registries. RESULTS: Replies were obtained from 15 countries from 5 of the world continents. Overall donation rate varied between 9 and 35 per million inhabitants. The number of pediatric LTs was 4 to 9 per million inhabitants younger than 18 years for 13 of the 15 respondents. In children younger than 2 years mortality on the waiting list (WL) varied between 0 and 20%. In the same age group, there were large differences in the ratio of living donor LT to deceased donor LT and in the ratio of split liver segments to whole liver. These differences were associated with possible discrepancies in WL mortality. CONCLUSIONS: Similarities but also differences between countries were detected. The described data may be of importance when trying to reduce WL mortality in the youngest children.


Asunto(s)
Gastroenterología/legislación & jurisprudencia , Política de Salud , Trasplante de Hígado/legislación & jurisprudencia , Pediatría/legislación & jurisprudencia , Obtención de Tejidos y Órganos/legislación & jurisprudencia , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Listas de Espera/mortalidad
15.
Adv Exp Med Biol ; 1125: 85-100, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30578461

RESUMEN

Pediatric obesity is rising worldwide leading the worrying phenomenon of nonalcoholic fatty liver disease (NAFLD) to shift into one of the most frequent causes of chronic liver illness in childhood. Occurrence of NAFLD depends on several factors such as the geographical area and the diagnostic modalities used; overall it ranges between 3% and 10% of pediatric population, increasing up to 70% in patients with metabolic comorbidities (Manco M, Bottazzo G, DeVito R et al, J Am Coll Nutr 27:667-676, 2008).Recent findings have related the intestinal microbiota to a plethora of pathological conditions, including type 2 diabetes (T2D), obesity, and nonalcoholic steatohepatitis (NASH). One of the emerging areas of the study is the link between liver diseases and gut microbiome, which has added new information to the understanding of the so-called gut-liver axis.In order to address the role of gut microbiome in NAFLD onset and progression, it is necessary to "decipher" operational codes for microbiome investigation within the context of advanced laboratory medicine to capture microbiome features and, hence, to address the function of the intestinal microbiome within the gut microbiota-liver axis.Results of these investigations have allowed the beginning of implementing the usage of probiotics and symbiotics in the medical approach of obesity and NAFLD in adults and children. Several randomized clinical trials (RCTs) have been already published on fecal microbiota transplantation (FMT), T2D, NASH, and inflammatory bowel disease (IBD).This review proposes to describe the current state of knowledge on the ways fatty liver diseases can be addressed with nutritional interventions, probiotics, symbiotics, and FMT.


Asunto(s)
Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico/terapia , Probióticos/uso terapéutico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Int J Mol Sci ; 20(14)2019 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-31337151

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a complex disease ranging from steatosis to non-alcoholic steatohepatitis (NASH). Galectin-3 (Gal-3), which is a ß-galactoside binding protein, has been associated with liver fibrosis, but its role in NAFLD remains elusive. We investigated the expression of Gal-3 in liver resident cells and its potential association with liver damage in 40 children with biopsy-proven NAFLD. We found that several liver cells expressed Gal-3. The number of total Gal-3 positive cells decreased with the severity of disease and the cells were correlated with the presence of steatosis and the diagnosis of NASH. CD68 macrophages expressed Gal-3 but the number CD68/Gal-3 positive cells was significantly reduced in patients diagnosed with steatosis and NASH. Triple CD68/CD206/Gal-3, which represented the subpopulation of M2 macrophages, were mainly present in patients without NASH, and clearly reduced in patients with steatosis and NASH. On the contrary, the number of α-smooth muscle actin (SMA)/Gal-3 positive cells increased with the severity of fibrosis in children with NAFLD. Our data demonstrated that the number of Gal-3 positive cells was associated with tissue damage in different ways, which suggests a dual role of this protein in the pathogenesis of pediatric NAFLD, even if the role of Gal-3 deserves further studies.


Asunto(s)
Galectina 3/metabolismo , Hepatocitos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Adolescente , Factores de Edad , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Conductos Biliares/metabolismo , Biomarcadores , Biopsia , Proteínas Sanguíneas , Niño , Femenino , Galectinas , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Pruebas de Función Hepática , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/etiología , Pronóstico , Índice de Severidad de la Enfermedad
17.
Semin Liver Dis ; 38(1): 1-13, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29471561

RESUMEN

Nonalcoholic steatohepatitis, a progressive form of nonalcoholic fatty liver disease (NAFLD), is one of the most common hepatic diseases in children who present with particular risk factors including obesity, sedentary lifestyle, and/or a predisposing genetic background. The worldwide prevalence of NAFLD in children is a worrying phenomenon because this disease is closely associated with the development of both cirrhosis and cardiometabolic syndrome in adulthood. To date, the etiopathogenesis of primary NAFLD in children is unknown. Understanding the pathogenetic mechanisms provides the basis to characterize early predictors of the disease and noninvasive diagnostic tools and to design novel specific treatments and possible management strategies. Despite a few clinical trials on the use of antioxidants combined with lifestyle intervention for NAFLD, no treatment exists for children with NAFLD. In this review, the authors provide an overview of current concepts in epidemiology, histological features, etiopathogenesis, diagnosis, and treatment of NAFLD in pediatric population.


Asunto(s)
Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad Infantil/epidemiología , Adolescente , Adulto , Edad de Inicio , Anciano , Niño , Preescolar , Comorbilidad , Progresión de la Enfermedad , Femenino , Humanos , Lactante , Recién Nacido , Hígado/fisiopatología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Enfermedad del Hígado Graso no Alcohólico/terapia , Obesidad Infantil/diagnóstico , Obesidad Infantil/fisiopatología , Obesidad Infantil/terapia , Prevalencia , Pronóstico , Factores de Riesgo , Conducta Sedentaria , Adulto Joven
18.
J Pediatr ; 194: 100-108.e3, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29198531

RESUMEN

OBJECTIVES: To investigate whether the modulation of local cellular cross-talks and the modification of hepatic adipocytokine expression could mechanistically explain the improvement of liver histopathology after laparoscopic sleeve gastrectomy (LSG) in adolescents with nonalcoholic fatty liver disease (NAFLD). STUDY DESIGN: Twenty obese (body mass index of ≥35 kg/m2) adolescents who underwent LSG and with biopsy-proven NAFLD were included. At baseline (T0) and 1 year after treatment, patients underwent clinical evaluation, blood tests, and liver biopsy. Hepatic progenitor cells, hepatic stellate cells (HSCs), macrophages, and adipocytokines were evaluated by immunohistochemistry and immunofluorescence. RESULTS: Liver biopsy samples after LSG demonstrated a significant improvement of NAFLD Activity Score and fibrosis. Immunohistochemistry indicated a significant reduction of hepatocyte cell cycle arrest, ductular reaction, activated HSC, and macrophage number after LSG compared with T0. The activation state of HSC was accompanied by modification in the expression of the autophagy marker LC3. Hepatocyte expression of adiponectin was significant higher after LSG than into T0. Moreover, LSG caused decreased resistin expression in Sox9+ hepatic progenitor cells compared with T0. The number of S100A9+ macrophages was also reduced by LSG correlating with resistin expression. Finally, serum levels of proinflammatory cytokines significantly correlated with macrophages and activated HSC numbers. CONCLUSIONS: The histologic improvement induced by LSG is associated with the reduced activation of local cellular compartments (hepatic progenitor cells, HSCs, and macrophages), thus, strengthening the role of cellular interactions and hepatic adipocytokine production in the pathogenesis of NAFLD.


Asunto(s)
Adipoquinas/fisiología , Gastrectomía , Hepatocitos/fisiología , Laparoscopía , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad Infantil/cirugía , Adolescente , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Cirrosis Hepática/terapia , Masculino , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/terapia , Obesidad Infantil/complicaciones , Obesidad Infantil/patología
19.
Hepatology ; 66(6): 1885-1893, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28741298

RESUMEN

The interferon (IFN) lambda 3/4 (IFNL3/4) locus, influencing innate immunity regulation, has been associated with the severity of hepatitis and fibrosis progression during chronic hepatitis C infection, while contrasting results were reported in nonalcoholic fatty liver disease. In this study, we examined whether rs12979860 and the linked causal rs368234815 variant encoding for the alternative IFNL4 protein variant are associated with liver fibrosis and damage in a large multicenter cohort of patients at risk of nonalcoholic steatohepatitis. To clarify the mechanism, we also evaluated the impact on IFN-stimulated gene hepatic expression in a subset of patients. We considered 946 consecutive Italian individuals at risk of nonalcoholic steatohepatitis with liver histology evaluated according to Kleiner. The rs368234815 TT>δG, rs12979860 C>T, and patatin-like phospholipase-3 rs738409 C>G polymorphisms were genotyped; and IFN-stimulated gene hepatic expression (n = 16) was tested by TaqMan assays. We found that the rs368234815 TT allele was independently associated with severe F3-F4 fibrosis (odds ratio, 1.53; 95% confidence interval, 1.15-2.31; P = 0.005) and with severe (grade 2-3) lobular necroinflammation (odds ratio, 1.47; 95% confidence interval, 1.14-1.88; P = 0.002). The impact of rs368234815 on liver damage was generally more marked in nonobese individuals, where association with severe fibrosis, necroinflammation, and nonalcoholic steatohepatitis was observed (P < 0.05). IFN-stimulated genes were hypo-expressed in the liver of patients carrying the IFNL4 rs368234815 TT/TT genotype (P < 0.05). Similar results were observed when considering the rs12979860 polymorphism, which was in high linkage disequilibrium with rs368234815 (R2 = 0.87). CONCLUSION: The IFNL4 genotype is associated with severity of fibrosis in nonalcoholic fatty liver disease patients of European ancestry, likely by modulating the activation of innate immunity and necroinflammation. (Hepatology 2017;66:1885-1893).


Asunto(s)
Interleucinas/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Adulto , Femenino , Fibrosis , Expresión Génica , Humanos , Hígado/metabolismo , Hígado/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Adulto Joven
20.
Hepatology ; 65(2): 451-464, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27028797

RESUMEN

There is evidence that nonalcoholic fatty liver disease (NAFLD) is affected by gut microbiota. Therefore, we investigated its modifications in pediatric NAFLD patients using targeted metagenomics and metabolomics. Stools were collected from 61 consecutive patients diagnosed with nonalcoholic fatty liver (NAFL), nonalcoholic steatohepatitis (NASH), or obesity and 54 healthy controls (CTRLs), matched in a case-control fashion. Operational taxonomic units were pyrosequenced targeting 16S ribosomal RNA and volatile organic compounds determined by solid-phase microextraction gas chromatography-mass spectrometry. The α-diversity was highest in CTRLs, followed by obese, NASH, and NAFL patients; and ß-diversity distinguished between patients and CTRLs but not NAFL and NASH. Compared to CTRLs, in NAFLD patients Actinobacteria were significantly increased and Bacteroidetes reduced. There were no significant differences among the NAFL, NASH, and obese groups. Overall NAFLD patients had increased levels of Bradyrhizobium, Anaerococcus, Peptoniphilus, Propionibacterium acnes, Dorea, and Ruminococcus and reduced proportions of Oscillospira and Rikenellaceae compared to CTRLs. After reducing metagenomics and metabolomics data dimensionality, multivariate analyses indicated a decrease of Oscillospira in NAFL and NASH groups and increases of Ruminococcus, Blautia, and Dorea in NASH patients compared to CTRLs. Of the 292 volatile organic compounds, 26 were up-regulated and 2 down-regulated in NAFLD patients. Multivariate analyses found that combination of Oscillospira, Rickenellaceae, Parabacteroides, Bacteroides fragilis, Sutterella, Lachnospiraceae, 4-methyl-2-pentanone, 1-butanol, and 2-butanone could discriminate NAFLD patients from CTRLs. Univariate analyses found significantly lower levels of Oscillospira and higher levels of 1-pentanol and 2-butanone in NAFL patients compared to CTRLs. In NASH, lower levels of Oscillospira were associated with higher abundance of Dorea and Ruminococcus and higher levels of 2-butanone and 4-methyl-2-pentanone compared to CTRLs. CONCLUSION: An Oscillospira decrease coupled to a 2-butanone up-regulation and increases in Ruminococcus and Dorea were identified as gut microbiota signatures of NAFL onset and NAFL-NASH progression, respectively. (Hepatology 2017;65:451-464).


Asunto(s)
Microbioma Gastrointestinal/genética , Enfermedad del Hígado Graso no Alcohólico/microbiología , Obesidad/microbiología , Adolescente , Análisis de Varianza , Estudios de Casos y Controles , Niño , Hígado Graso/microbiología , Hígado Graso/fisiopatología , Femenino , Humanos , Masculino , Análisis Multivariante , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Obesidad/fisiopatología , Pediatría , Proteogenómica/métodos , Valores de Referencia , Sensibilidad y Especificidad
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