Decreased energy and phosphorylation status in the liver of lung cancer patients with weight loss

Background/Aims: Altered energy status has been reported in the liver of tu mour-bearing animals, but data on energy status in humans are scarce. There fore, bioenergetics in tumour-free liver of lung cancer patients were monit ored using P-31 magnetic resonance spectroscopy (MRS) with infusion of L-al anine as a gluconeogenic challenge. Methods: Twenty-one overnight-fasted lung cancer patients without liver met astases, with (CaWL) or without weight loss (CaWS), and 12 healthy control subjects (C) were studied. Hepatic energy status was monitored before and d uring an i.v. L-alanine infusion of 1.4-2.8 mmol/kg + 2.8 mmol . kg(-1). h( -1) for 90 min by P-31 MR spectroscopy. Results: Baseline levels of ATP in WL lung cancer patients, expressed relat ive to total MR-detectable phosphate, were reduced (CaWL, 9.5+/-0.9% vs. Ca WS, 12.6+/-0.8% and C, 12.4+/-0.8%; p<0.05) and inversely correlated with t he degree of weight loss in lung cancer patients (r=-0.46, p=0.03), P-i/ATP ratios were increased (p<0.05), indicating reduced liver phosphorylation s tatus. During L-alanine infusion, ATP levels decreased in all groups (p<0.0 5); in CaWL, ATP levels were lower at all time-points between 0-90 min as c ompared to both CaWS and C (p<0.05), P-i/ATP ratios were significantly high er after 70-90 min of L-alanine infusion in CaWL compared to CaWS and C (p< 0.05). Conclusions: Hepatic ATP and phosphorylation status are reduced in WL lung cancer patients, in contrast to WS patients and healthy subjects, and conti nue to decrease during infusion of a gluconeogenic substrate, suggesting im paired energy regenerating capacity in these patients.