Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with...Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.展开更多
AIM: To analyze the associations of pancreatic fat with other fat depots and β-cell function in pediatric nonalcoholic fatty liver disease(NAFLD).METHODS: We examined 158 overweight/obese children and adolescents, 80...AIM: To analyze the associations of pancreatic fat with other fat depots and β-cell function in pediatric nonalcoholic fatty liver disease(NAFLD).METHODS: We examined 158 overweight/obese children and adolescents, 80 with NAFLD [hepatic fat fraction(HFF) ≥ 5%] and 78 without fatty liver. Visceral adipose tissue(VAT), pancreatic fat fraction(PFF) and HFF were determined by magnetic resonance imaging. Estimates of insulin sensitivity were calculated using the homeostasis model assessment of insulin resistance(HOMA-IR), defined by fasting insulin and fasting glucose and whole-body insulin sensitivity index(WBISI), based on mean values of insulin and glucose obtained from oral glucose tolerance test and the corresponding fasting values. Patients were considered to have prediabetes if they had either:(1) impaired fasting glucose, defined as a fasting glucose level ≥ 100 mg/d L to < 126 mg/d L;(2) impaired glucose tolerance, defined as a 2 h glucose concentration between ≥ 140 mg/d L and < 200 mg/d L; or(3) hemoglobin A1 c value of ≥ 5.7% to < 6.5%.RESULTS: PFF was significantly higher in NAFLD patients compared with subjects without liver involvement. PFF was significantly associated with HFF and VAT, as well as fasting insulin, C peptide, HOMA-IR, and WBISI. The association between PFF and HFF was no longer significant after adjusting for age, gender, Tanner stage, body mass index(BMI)-SD score, and VAT. In multiple regression analysis withWBISI or HOMA-IR as the dependent variables, against the covariates age, gender, Tanner stage, BMI-SD score, VAT, PFF, and HFF, the only variable significantly associated with WBISI(standardized coefficient B,-0.398; P = 0.001) as well as HOMA-IR(0.353; P = 0.003) was HFF. Children with prediabetes had higher PFF and HFF than those without. PFF and HFF were significantly associated with prediabetes after adjustment for clinical variables. When all fat depots where included in the same model, only HFF remained significantly associated with prediabetes(OR = 3.38; 95%CI: 1.10-10.4; P = 0.034).CONCLUSION: In overweight/obese children with NAFLD, pancreatic fat is increased compared with those without liver involvement. However, only liver fat is independently related to prediabetes.展开更多
文摘Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.
基金Supported by Sapienza University of Rome(Progetti di Ricerca Universitaria 2011-2012)
文摘AIM: To analyze the associations of pancreatic fat with other fat depots and β-cell function in pediatric nonalcoholic fatty liver disease(NAFLD).METHODS: We examined 158 overweight/obese children and adolescents, 80 with NAFLD [hepatic fat fraction(HFF) ≥ 5%] and 78 without fatty liver. Visceral adipose tissue(VAT), pancreatic fat fraction(PFF) and HFF were determined by magnetic resonance imaging. Estimates of insulin sensitivity were calculated using the homeostasis model assessment of insulin resistance(HOMA-IR), defined by fasting insulin and fasting glucose and whole-body insulin sensitivity index(WBISI), based on mean values of insulin and glucose obtained from oral glucose tolerance test and the corresponding fasting values. Patients were considered to have prediabetes if they had either:(1) impaired fasting glucose, defined as a fasting glucose level ≥ 100 mg/d L to < 126 mg/d L;(2) impaired glucose tolerance, defined as a 2 h glucose concentration between ≥ 140 mg/d L and < 200 mg/d L; or(3) hemoglobin A1 c value of ≥ 5.7% to < 6.5%.RESULTS: PFF was significantly higher in NAFLD patients compared with subjects without liver involvement. PFF was significantly associated with HFF and VAT, as well as fasting insulin, C peptide, HOMA-IR, and WBISI. The association between PFF and HFF was no longer significant after adjusting for age, gender, Tanner stage, body mass index(BMI)-SD score, and VAT. In multiple regression analysis withWBISI or HOMA-IR as the dependent variables, against the covariates age, gender, Tanner stage, BMI-SD score, VAT, PFF, and HFF, the only variable significantly associated with WBISI(standardized coefficient B,-0.398; P = 0.001) as well as HOMA-IR(0.353; P = 0.003) was HFF. Children with prediabetes had higher PFF and HFF than those without. PFF and HFF were significantly associated with prediabetes after adjustment for clinical variables. When all fat depots where included in the same model, only HFF remained significantly associated with prediabetes(OR = 3.38; 95%CI: 1.10-10.4; P = 0.034).CONCLUSION: In overweight/obese children with NAFLD, pancreatic fat is increased compared with those without liver involvement. However, only liver fat is independently related to prediabetes.
