Evidence for altered hepatic gluconeogenesis in patients with cirrhosis using in vivo 31-phosphorus magnetic resonance spectroscopy

Abstract

Background and aims-Alterations in gluconeogenesis in the diseased liver can be assessed non-invasively using magnetic resonance spectroscopy by measuring changes in phosphomonoester resonance which contains information regarding several metabolites, including the phosphorylated intermediates of the gluconeogenic pathway. Methods- 31P magnetic resonance spectroscopy was used to determine changes in phosphomonoesters following bolus infusions of 2.8 mmol/kg L-alanine in five patients with functionally compensated cirrhosis and in five patients with functionally decompensated cirrhosis. Results-Compared with six healthy volunteers,baseline phosphomonoester values were elevated by 35% (p<0.05) in the compensated cirrhosis group and by 57% (p<0.01) in the decompensated cirrhosis group. Following alanine infusion, phosphomonoesters in healthy volunteers increased by 46% from baseline values (p<0.01), in patients with compensated cirrhosis by 27% (p<0.02) but those with decompensated cirrhosis showed no increase from baseline. There was a reduction in the percentage of inorganic phosphate signal in all subjects. Conclusions-By analysing changes in phosphomonoester and inorganic phosphate resonances it is possible to discern clear metabolic diVerences between healthy volunteers and patients with cirrhosis of varying severity using magnetic resonance spectroscopy. Those patients with functionally decompensated cirrhosis have higher percentage baseline phosphomonoester values but the absence of phosphomonoester elevation following L-alanine infusion suggests that they are unable to mount a significant metabolic response with a progluconeogenic stimulus. (Gut 2001;49:557-564)

Quantitative hepatic phosphorus-31 magnetic resonance spectroscopy in compensated and decompensated cirrhosis

“…Altered hepatic bioenergetics have long been implicated as contributing to the disturbances associated with cirrhosis (4,17,36,37). However, the present study is the first to report that hepatic ATP levels in vivo are significantly lower in patients with decompensated cirrhosis.…”

Nonalcoholic Fatty Liver Disease: Detection of Elevated Nicotinamide Adenine Dinucleotide Phosphate with in Vivo 3.0-T31P MR Spectroscopy with Proton Decoupling

“…Researchers have found alterations in phospholipid metabolites in a wide variety of liver diseases with in vivo ( 4,(12)(13)(14)(15)(16) and in vitro ( 4,17 ) 31 P MR spectroscopy. The precise metabolic abnormalities responsible for 31 P MR spectroscopy fi ndings in patients with these liver diseases still are not completely understood.…”

Nutrición parenteral en situaciones clínicas especiales

“…En pacientes pediátricos candidatos a trasplante se recomienda un soporte nutricional agresivo para mejorar el pronóstico (47). No hay estudios controlados que determinen el aporte óptimo de nutrientes en el paciente pediátrico con enfermedad hepática, por lo que muchas de las recomendaciones se extrapolan de estudios en adultos (50,51).…”

“…Es prioritario mantener aportes de glucosa (6-8 mg/kg/min) para prevenir la hipoglucemia (secundaria a la limitación del almacenamiento de glucógeno y de la neoglucogénesis hepática) (51).…”