Bioelectric impedance spectroscopy underestimates fat-free mass compared to dual energy X-ray absorptiometry in incurable cancer patients.

BACKGROUND/OBJECTIVES: Weight loss is frequently seen in advanced cancer. Bioelectrical impedance spectroscopy (BIS) is a convenient method for estimating body composition. We examined in a prospective, comparative study if BIS could accurately estimate fat-free mass (FFM) in cancer patients compared to dual-energy X-ray absorptiometry (DXA). SUBJECTS/METHODS: The study was based on 132 consecutive incurable cancer patients with solid tumours in a University hospital outpatient clinic. Comparison of FFM from DXA and BIS with standard and revised equations. Bland-Altman plots, t-tests and linear regression analysis were used to evaluate agreement and differences between methods. RESULTS: BIS significantly underestimated mean FFM with 7.6+/-4.7 kg compared to DXA (P<0.001). Bias was significantly correlated to % weight loss (r=0.32), systemic inflammation as measured by C-reactive protein (r=0.29), malnutrition as assessed by low insulin-like growth factor-1 (r=-0.23) and inversely to the per cent body fat estimated by DXA (P=-0.61) and body mass index (BMI; r=-0.30). Revised BIS equations taking BMI into account reduced bias significantly but still with great individual variation. CONCLUSIONS: BIS by standard equations grossly underestimates FFM compared to DXA in cancer patients. This bias is related to weight loss, malnutrition and systemic inflammation. Revised equations improved FFM estimates, but with large individual variation. Thus, BIS with standard equations is not suitable to estimate FFM in patients with cachexia, inflammation and malnutrition.

The role of diet components, gastrointestinal factors, and muscle innervation on activation of protein synthesis in skeletal muscles following oral refeeding.

The aim of this study was to quantify the effect of oral refeeding on the synthesis of soluble and contractile proteins in skeletal muscles, and to evaluate to what extent diet components (carbohydrate, fat, amino acids), hormones (insulin, IGF-I, GIP), Ca2+ flux, polyamine synthesis, cyclooxygenase activity, and muscle innervation are related to activation of protein synthesis at the translational level following oral refeeding. Adult, weight-stable, non-growing mice (C57B1) were used in starvation/refeeding experiments with oral chow. Growing rats (150 g) were used in parenteral refeeding experiments. Protein synthesis was measured in vivo in mixed muscles (phenylalanine flooding), in phasic EDL muscles (in vitro), and in cultured L-6 muscle cells. Overnight starvation reduced synthesis of soluble proteins by 37 +/- 8% (from 0.242 +/- 0.025 to 0.151 +/- 0.009 microgram-1.mg-1) and contractile proteins by 55 +/- 6% (from 0.148 +/- 0.018 to 0.068 microgram-1.mg-1) (P < 0.01). Soluble proteins with a basic net charge were more sensitive to nutrition compared to neutral and acidic proteins. Somatostatin treatment before refeeding attenuated muscle protein synthesis by 15% (P < 0.02). Mechanical stimulation of the gastrointestinal tract (bulk feeding) did not activate protein synthesis in muscles, while i.v. or i.p. provision of nutrients did. Oral refeeding normalized rates of protein synthesis within 3 h (P < 0.01), independently of intact muscle innervation, Ca2+ flux, polyamine synthesis, and cyclooxygenase activity in the skeletal muscles, while it was dependent on a complete substrate composition of the oral diet. Our results support the hypothesis that amino acids, probably in concerted action with locally produced tissue IGF-I, stimulate protein synthesis in skeletal muscles during refeeding.

Role of insulin and IGF-I in activation of muscle protein synthesis after oral feeding.

The aim was to evaluate the role of insulin and insulin-like growth factor I (IGF-I) in activation of muscle protein synthesis after oral feeding. Synthesis rate of globular and myofibrillar proteins in muscle tissue was quantified by a flooding dose of radioactive phenylalanine. Muscle tissue expression of IGF-I mRNA was measured. Normal (C57 Bl) and diabetic mice (type I and type II) were subjected to an overnight fast (18 h) with subsequent refeeding procedures for 3 h with either oral chow intake or provision of insulin, IGF-I, glucose, and amino acids. Anti-insulin and anti-IGF-I were provided intraperitoneally before oral refeeding in some experiments. An overnight fast reduced synthesis of both globular (38 +/- 3%) and myofibrillar proteins (54 +/- 3%) in skeletal muscles, which was reversed by oral refeeding. Muscle protein synthesis, after starvation/ refeeding, was proportional and similar to changes in skeletal muscle IGF-I mRNA expression. Diabetic mice responded quantitatively similarly to starvation/refeeding in muscle protein synthesis compared with normal mice (C57 Bl). Both anti-insulin and anti-IGF-I attenuated significantly the stimulation of muscle protein synthesis in response to oral feeding, whereas exogenous provision of either insulin or IGF-I to overnight-starved and freely fed mice did not clearly stimulate protein synthesis in skeletal muscles. Our results support the suggestion that insulin and IGF-I either induce or facilitate the protein synthesis machinery in skeletal muscles rather than exerting a true stimulation of the biosynthetic process during feeding.

Evaluation of mechanisms behind elevated energy expenditure in cancer patients with solid tumours.

The aim of this study was to demonstrate significant factors behind elevated resting energy expenditure in weight-losing cancer patients. Therefore, weight-losing cancer patients (n = 60), with normal liver and kidney function tests, were randomized to receive one of four drug treatments for 5 days: (a) Propranolol 80 mg x 2 (beta-adrenoceptor blockade); (b) Indomethacin 50 mg x 2 (prostaglandin synthesis inhibition); (c) Morphine 5 mg x 3 (pain relief) or (d) Placebo x 2. A reference group of healthy well-nourished individuals were examined outside the formal randomization protocol and they received Propranolol 80 mg x 2. The cancer patients were randomized by a computer based algorithm stratifying for measured resting energy expenditure (REE), body composition, biochemical tests, previous therapy, tumour type and tumour stage. Resting energy expenditure was measured by indirect calorimetry in the morning after an overnight fast before and after drug treatment. beta-blockade reduced REE significantly in cancer patients from 1416 +/- 95 kcal day-1 to 1160 +/- 63 kcal day-1 (P < 0.02) and from 1472 +/- 69 vs, 1398 +/- 63 kcal day-1 (P < 0.01) in the well-nourished reference individuals. The reduction found in cancer patients (10%) was significantly larger than that in the group of reference patients (5%), (P < 0.01). Indomethacin, morphine or placebo did not induce any significant alteration in energy expenditure in our cancer patients. Propranolol treatment was associated with a significant reduction in plasma concentrations of free fatty acids (FFA), but not in plasma glycerol.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of the adrenals in the acute phase response to interleukin-1 and tumor necrosis factor-alpha.

The purpose of this study was to investigate the role of the adrenals, particularly the glucocorticoids, in the acute phase response following daily injections for 5 days of recombinant human interleukin-1 alpha,beta and tumor necrosis factor-alpha (TNF alpha). Adult weight-stable freely fed or pair-fed (to cytokine-injected mice) mice (C57Bl/6J) with and without adrenals were used. Adrenalectomized animals showed a sensitivity to both IL-1 alpha and -1 beta (40 ng IL-1/day) greater than 10-fold higher than that of normal mice (420 ng IL-1/day) in regard to mortality and anorexia. Microscopic examination of tissue specimens from adrenalectomized IL-1 alpha,beta-injected mice did not reveal any histologic alterations in lung, kidney, liver, brain, or gastrointestinal tract to explain the mortality. This mortality was not prevented by physiologic replacement doses of hydrocortisone (10-20 micrograms/day); however, a pharmacological dose of 2.5 mg hydrocortisone/day abolished completely the increased toxicity to IL-1 alpha,beta and the anorectic response to IL-1 alpha,beta and TNF alpha. Increased toxicity (mortality) was not observed in adrenalectomized animals with TNF alpha at the dose interval used (450 ng TNF alpha/day and lower). The hepatic acute phase response (liver weight and RNA and liver protein content) was increased by both IL-1 alpha,beta and TNF alpha in a glucocorticoid-independent way. The cytokine-induced alterations of plasma concentrations of acute phase proteins (serum amyloid P, transferrin, complement C3) were significantly dependent on glucocorticoids, while the decline in plasma albumin was not.(ABSTRACT TRUNCATED AT 250 WORDS)

Pretranslational regulation of albumin synthesis in tumor-bearing mice. The role of anorexia and undernutrition.

Hepatic albumin synthesis, serum albumin turnover, and hepatic albumin messenger RNA (mRNA) content were evaluated in mice bearing a transplantable low differentiated tumor (MCG 101). Results obtained on tumor-bearing mice were compared with results obtained from non-tumor-bearing animals that were either freely fed, food restricted so that their body composition was similar to tumor-bearing animals (pair-weighed), fed a protein-free diet for 5 days, or fasted for 48 hours. Tumor-bearing animals became hypoalbuminemic (33 +/- 5 vs. 44 +/- 3 g/L in freely fed mice), which could be explained by both depressed albumin synthesis (1.95% +/- 0.20% vs. 2.67% +/- 0.27%/h in freely fed mice) and increased albumin degradation. Pair-weighed and protein-calorie malnourished controls had reductions in albumin synthesis (1.81% +/- 0.18% and 1.67% +/- 0.17%/h, respectively) similar to tumor-bearing animals, and the starved controls had the lowest synthetic rates (1.07% +/- 0.10%/h). Albumin degradation was increased only in tumor-bearing animals. Hepatic albumin mRNA in undernourished animals was less (tumor bearing, 32% +/- 5%; pair weighed, 47% +/- 4%; 48 hours fasted, 18% +/- 2%; and protein-calorie malnourished, 26% +/- 3%) than 50% of the mRNA content in the livers of freely fed control mice. Messenger RNA-directed synthesis of albumin in vitro was also depressed to a variable degree in tumor-bearing and malnourished non-tumor-bearing controls. The hypoalbuminemia in tumor-bearing animals could not be prevented by daily injections of a prostaglandin synthesis inhibitor (indomethacin, 1 microgram/g body wt), but the hepatic acute phase protein serum amyloid P decreased from 157 +/- 12 to 103 +/- 9 micrograms/mL in indomethacin-treated tumor-bearing mice (P less than 0.01). It is concluded that increased albumin degradation seen in tumor-bearing animals cannot be explained by associated malnutrition, whereas tumor-associated malnutrition can explain to a large extent the depressed albumin synthesis. Decreased albumin synthesis in tumor-bearing animals correlated in part with a decreased quantity of liver albumin mRNA. The results of the current study are consistent with either a reduced transcription of the albumin gene or a change in albumin mRNA processing and stability communicated by anorexia and malnutrition.

Anticachectin/tumor necrosis factor-alpha antibodies attenuate development of cachexia in tumor models.

C57BL/6 mice bearing either a transplantable methylcholanthrene-induced sarcoma or Lewis lung adenocarcinoma were passively immunized every other day with a rabbit immunoglobulin fraction raised against murine cachectin/tumor necrosis factor-alpha. Mice bearing methylcholanthrene-induced sarcoma developed tumor-associated hypophagia that was attenuated by anticachectin immunoglobulin treatment. In the same tumor-bearing animals, anticachectin treatment also significantly reduced the extent of carcass protein and fat loss, and reduced tumor weight. Mice bearing Lewis lung adenocarcinoma did not develop significant anorexia or carcass lean tissue depletion as tumor growth progressed, but they lost carcass lipid. Treatment of Lewis lung adenocarcinoma bearing mice with anticachectin antibodies diminished the degree of carcass lipid depletion and prevented plasma hypertriglyceridemia. However, in both tumor models, anticachectin treatment did not affect either the development of anemia, hypoalbuminemia or the increase in serum amyloid P concentrations seen with increasing tumor burden. We conclude that an endogenous cachectin response, inhibitable by exogenously administered antibody, contributes to anorexia and to changes in body fat and protein metabolism in these tumor-bearing animals. Neutralizing endogenous cachectin production with antibodies offers the potential to reduce tissue wasting that is frequently associated with neoplastic disease, but it does not appear to affect all of the hematologic and acute phase responses in these murine tumor models.

Appearance of hybridoma growth factor/interleukin-6 in the serum of mice bearing a methylcholanthrene-induced sarcoma.

Serum concentrations of hybridoma growth factor/interleukin-6 progressively increased in mice bearing a transplantable methylcholanthrene-induced sarcoma with tumor growth. Elevated HGF/interleukin-6 concentrations were also positively correlated with increased serum concentrations of the hepatic acute phase reactant protein, amyloid P. Daily Indomethacin treatment of sarcoma-bearing mice prolonged survival and reduced the magnitude of the serum amyloid P response, but failed to attenuate either tumor growth or serum HGF/interleukin-6 responses. Since previous studies have demonstrated that neither interleukin-1 nor tumor necrosis factor-alpha can be detected in the serum of these sarcoma-bearing mice, and that HGF/interleukin-6 is a principal mediator of the hepatic acute phase response, we conclude that circulating HGF/interleukin-6 may contribute significantly to the host responses which accompany experimentally-introduced cancer. Furthermore, prostanoid inhibition does not appear to regulate the synthesis and release of HGF/interleukin-6 during tumor growth.

Regulation of food intake and hepatic protein synthesis by recombinant-derived cytokines.

During inflammation, activated monocytes and lymphocytes synthesize and release many soluble protein mediators, such as interleukin (IL) 1, tumor necrosis factor-alpha, and IL-2. It is presently unclear which cytokines, if any, contribute to the anorexia and hepatic protein changes frequently seen during inflammation. To evaluate their potential role, food intake and liver and plasma protein synthesis were determined in both endotoxin-sensitive C57Bl/6j mice and endotoxin-resistant C3H/HeJ mice given either crude secretory products of Staphylococcus albus-stimulated human blood monocytes or murine recombinant IL-1-alpha, human recombinant IL-1-alpha or -beta, human recombinant tumor necrosis factor-alpha, or human IL-2. When given intraperitoneally to healthy animals, 2,000 lymphocyte-activating factor U/day of secretory products of activated human blood monocytes or recombinant murine IL-1-alpha depressed spontaneous food intake by 42 and 53%, respectively. Human IL-1-alpha and -beta and human tumor necrosis factor-alpha produced smaller reductions in food intake. In contrast, human IL-2, when given in equimolar quantities, had no appreciable effect on food intake or body weight. Administration of crude secretory products of activated blood monocytes, recombinant IL-1, or tumor necrosis factor-alpha increased liver weight, protein, and RNA content. In addition, plasma protein synthesis was significantly increased, as were serum amyloid P concentrations. Administration of recombinant tumor necrosis factor-alpha resulted in IL-1 production by peritoneal adherent cells. However, IL-2 had no effect on any hepatic parameter.

Interleukin 1 and tumor necrosis factor do not regulate protein balance in skeletal muscle.

Recent studies have claimed that interleukin 1-containing preparations increase skeletal protein degradation similar to that seen during infection and inflammation. However, preparations employed have contained other products of activated macrophages, including tumor necrosis factor-alpha. In the present report, we investigated the capability of recombinant-derived murine and human interleukins 1-alpha and 1-beta and human tumor necrosis factor-alpha to affect skeletal protein synthesis and degradation both in vitro and in vivo. Partially purified products of Staphylococcus albus-stimulated human blood monocytes increased skeletal protein degradation both in vivo and in vitro. However, none of the recombinant interleukin 1 nor the human tumor necrosis factor-alpha preparations had any impact on skeletal protein balance. Both recombinant interleukin 1 and tumor necrosis factor-alpha stimulated the production of prostaglandin E2 (PGE2). Furthermore, a polyclonal antibody to human interleukin 1 eliminated the lymphoproliferative response to partially purified monocyte preparations (interleukin 1 activity), but failed to abrogate the increased skeletal protein degradation in vitro. This study demonstrates that although interleukin 1 and tumor necrosis factor-alpha induce a PGE2 response by skeletal muscle in vitro, some macrophage product distinct from either interleukin 1 or tumor necrosis factor-alpha is responsible for the accelerated skeletal protein degradation seen with partially purified human blood monocyte products. Elevated PGE2 levels do not appear to regulate skeletal protein balance in vitro.

Circulating interleukin 1 and tumor necrosis factor during inflammation.

It is proposed that interleukin 1 (IL 1) and tumor necrosis factor (TNF) alpha play central roles in the host's response to inflammation. Yet circulating concentrations have not been frequently measured in many inflammatory states. Serum levels of IL 1 and TNF were evaluated in mice with a tumor, sterile inflammation, endotoxinemia, or generalized peritonitis where an acute-phase protein response was documented. In tumor-bearing mice, no IL 1 or TNF could be detected despite marked increases in the serum concentration of the acute-phase reactant protein, amyloid P. In mice with peritonitis, induced by cecal ligation and perforation, or a turpentine-induced subcutaneous abscess, IL 1 but not TNF could be detected in the serum. Only expansion of the reticuloendothelial system with Corynebacterium parvum and subsequent challenge with endotoxin resulted in serum TNF appearance. The failure to observe IL 1 or TNF in any of the disorders could not be explained by inhibitors. Rather, the data suggest that a hepatic acute-phase protein response can occur during inflammatory states without the appearance of either IL 1 or TNF in the circulation. Circulating levels of both monokines do not appear to be a universal finding in inflammation.

Plasma protein synthesis in experimental cancer compared to paraneoplastic conditions, including monokine administration.

During tumor growth, there are characteristic alterations in the concentration and synthesis of various plasma proteins. The purpose of this study was to evaluate whether these changes are unique to a tumor-bearing state, or rather, they represent a generalized response to a paraneoplastic state mediated by the release of monokines or protein-calorie malnutrition. Plasma protein synthesis and concentrations in mice bearing a transplantable fibrosarcoma were compared to animals receiving either a terpentine abscess, Corynebacterium parvum administration, calorie-protein depletion, or administration of the recombinant-derived monokines, murine interleukin 1 alpha or human tumor necrosis factor-alpha. Tumor-bearing animals showed a significant increase in total plasma protein synthesis that was similar in magnitude to the increase seen following a terpentine abscess or after administration of interleukin 1 or tumor necrosis factor-alpha. Similarly, the pattern of protein synthesis and concentration, as determined by isoelectric focusing or sodium dodecyl sulphate-polyacrylamide gel electrophoresis, were similar, albeit not identical, among tumor-bearing animals and those receiving either a terpentine abscess, C. parvum and monokine administration. Serum amyloid P concentrations were markedly elevated in tumor-bearing animals, as they were in animals after a sterile abscess and following interleukin 1 administration, as well as to a lesser extent tumor necrosis factor-alpha administration. We can therefore conclude that the majority of changes in plasma protein concentration and synthesis seen in this tumor-bearing model are similar to those seen during an acute inflammation and can be reproduced to a large extent by the administration of the monokines, interleukin 1 alpha or tumor necrosis factor-alpha.

Optimal nutritional indexes in cancer patients.

This paper reviews various parameters that are used to assess the nutritional and functional status of cancer patients. Available information shows that the nutritional status of cancer patients is correlated with their overall prognosis and outcome. However, little information exists concerning the use of nutritional indexes to evaluate the effectiveness of nutritional rehabilitation of cancer patients. It is emphasized that we should concentrate on developing nutritional parameters to assess the functional improvement of patients rather than their body structure and composition.

Down-regulation of interleukin 1 production by macrophages of sarcoma-bearing mice.

Peritoneal macrophages from mice bearing a transplantable methylcholanthrene-induced sarcoma produced progressively less IL 1 as tumor burden increased. The loss of activity was not explained by the production of any inhibitor of the mouse thymocyte comitogen bioassay. Immune precipitation with a polyclonal antibody confirmed the decline in IL 1 appearance. Although tumor-bearing animals lost approximately 17% of their carcass mass, the reduced production of IL 1 was not satisfactorily explained by coexistent malnutrition, since similarly depleted non-tumor-bearing mice were capable of producing IL 1. In addition to an altered IL 1 production by macrophages of tumor-bearing mice, SDS-polyacrylamide gel electrophoresis and autoradiography revealed that the pattern of secretory protein synthesis from LPS-stimulated and unstimulated peritoneal macrophages differed between tumor-bearing and control animals. Administration of LPS to tumor-bearing mice early after tumor transplantation resulted in reduced tumor growth and prevented the down-regulation of in vitro IL 1 production by peritoneal macrophages. These findings demonstrate a specific defect in IL 1 production associated with increasing tumor burden. Further studies are required to determine whether this defect in IL 1 synthesis contributes to the increased tumor growth.

Body compositional changes in cancer patients.

Noninvasive and spectroscopic techniques already available and under further development in several laboratories will in the near future give us a greater amount of detailed information on changes in body compartments in disease and in response to therapeutic efforts. Such techniques should have the ability to measure directly components in an organ or tissue in contrast to most present and previous techniques that generally rely on derivation of components from a few direct measurements. Such derivations are unfortunately dependent on assumptions that are not possible to control in several circumstances.

Origins of emaciation in cancer patients.

Anorexia and elevated energy expenditure contributes to weight loss in cancer patients. Increased energy expenditure may explain 0.5-1.0 kg weight loss per month with regard to resting energy expenditure and even more with regard to total energy expenditure. The explanation behind elevated energy expenditure does not seem to be due to the tumour metabolism itself but rather to an increased host metabolic demand aimed at providing life-supporting protein synthesis and perhaps the immune system with energy. The trigger behind the activation of the synthesis of certain proteins is unknown. Only sparse information is available on the altered regulation of appetite in cancer disease. Changed metabolism and activity of neurotransmitters seem to be involved.