Liver diseases and caloric restriction.
Treatment of rapid weight loss in a donor with hepatic steatosis in living donor liver transplantation: a case report.
Yamanaka-Okumura H, Urano E, Kawaura A, Imura S, Utsunomiya T, Shimada M, Takeda E.
Hepatogastroenterology. 2012 May;59(115):869-71. doi: 10.5754/hge10237.
Department of Clinical Nutrition, University of Tokushina Graduate School, Tokushima, Japan.
The use of steatotic livers for transplantation is often associated with increased primary non-function. To reduce the risk of liver injury, steatosis of the donor liver in living donor liver transplantation (LDLT) was treated with restricted diet and exercise. A 21-year-old male donor, 167cm in height and 87kg in body weight, initially received a 1800kcal/day diet for 9 days which was then gradually reduced using a 1600kcal/day diet for 43 days, followed by a 1500kcal/day diet for one day and was finally maintained on a 1400kcal/day diet for 52 days. Daily exercise consumed 500kcal/day. The non-protein respiratory quotient (npRQ) gradually increased while the non-esterified fatty acids (NEFA) decreased during the course of the 105-day treatment. Consequently, the initial 80% steatosis was reduced to 10% and was accompanied by 13% weight loss for 81 days. The npRQ values and NEFA concentrations in the later period of dietary and exercise treatment were higher and lower, respectively, than in the early treatment period, indicating compensation through long-term treatment. Therefore, energy metabolism and NEFA levels represent important biomarkers for short-term intensive treatment by restricted diet and exercise in donors with hepatic steatosis.
Mechanisms of increased liver tissue repair and survival in diet-restricted rats treated with equitoxic doses of thioacetamide.
Toxicol Sci. 2003 Apr;72(2):272-82. Epub 2003 Mar 7.
Apte UM, Limaye PB, Desaiah D, Bucci TJ, Warbritton A, Mehendale HM.
Department of Toxicology, School of Pharmacy, The University of Louisiana at Monroe, Monroe, Louisiana 71209, USA.
Moderate dietary or caloric restriction (DR) modulates animal physiology in a beneficial fashion. Previously, we have reported an equitoxic dose experiment where liver injury in DR male Sprague-Dawley rats exposed to a low dose of thioacetamide (TA, 50 mg/kg) was similar to that observed in ad libitum fed (AL) rats exposed to a 12-fold higher dose (600 mg/kg). Paradoxically, the AL rats experienced 90% mortality while all of the DR rats, with the same amount of initial bioactivation-mediated liver injury, survived. The protection observed in the DR rats was due to efficient compensatory liver tissue repair, which was delayed and attenuated in the AL rats, leading to progression of liver injury. The objective
of the present study was to investigate the molecular mechanisms of the enhanced tissue repair in the DR rats upon equitoxic challenge with TA. Promitogenic mechanisms and mediators such as proinflammatory cytokines (TNF-alpha and IL-6), growth factors (TGF-alpha and HGF), and inducible nitric oxide synthase (iNOS) were estimated over a time course after equitoxic challenge (50 mg/kg to DR vs. 600 mg/kg to AL rats). Except for TNF-alpha, all other molecules were expressed earlier and in greater amount in the DR rats. IL-6 was 10-fold greater and peaked 12 h earlier; HGF also peaked 12 h sooner in the DR rats, when it was 2.5-fold greater than the value in the AL rats. TGF-alpha expression in livers of DR rats increased after TA administration and peaked at 24 h. In the AL rats, it was lower and peaked at 36 h. Diet restriction alone induced iNOS 2-fold in the DR rats and remained elevated until 12 h after TA administration, then declined thereafter. The lower iNOS activity in the AL rats further decreased after TA injection. DR rats exhibited higher apoptosis after thioacetamide administration, which further increased the efficiency of tissue repair. Taken together, these data indicate that even though the liver injury is near equal in AL and DR rats, sluggish signal transduction leads to delayed liver regeneration, progression of liver injury, and death in the AL rats. The equitoxic dose experiment indicates that stimulation of tissue repair is independent of the extent of initial liver injury and is governed by physiology of diet restriction. DR stimulates promitogenic signaling leading to a quick and timely response upon liver injury, arrest of progressive injury on one hand, and recovery from injury on the other, paving the way for survival of the DR rats. |
