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Background Energy homeostasis is mediated by the hypothalamus, whose inflammation-induced functional derangements contribute to the onset of anorexia in cancer. By using functional magnetic resonance imaging (fMRI), we determined the patterns of hypothalamic activation after oral intake in anorexic (A), non-anorexic (NA) cancer patients, and in controls (C). Methods Lung cancer patients were considered. Hypothalamic activation was recorded in A and NA patients and in C by fMRI, before (T0), immediately after (T1) the administration of an oral nutritional supplement, and after 15 min (T2). The grey of the hypothalamus and Blood Oxygen Level Dependent (BOLD) intensity were calculated and normalized for basal conditions. Interleukin (IL)-1, IL-6, tumour necrosis factor (TNF)-α, ghrelin, and leptin plasma levels were measured. A statistical parametric mapping was used. Results Thirteen lung cancer patients (7 M, 6 F; 9A, 4NA) and 2 C (1 M, 1 F) were enrolled. Controls had the lowest BOLD intensity. At all-time points, anorexic patients showed lower hypothalamic activity compared with NA (P

Cachexia and sarcopenia are conditions phenotypically characterized by muscle loss and represent a factor of poor prognosis, increasing patients' morbidity and mortality. Cachectic and sarcopenic patients often suffer from low quality of life, presenting lower muscle strength and appetite loss, which makes research on novel treatment strategies to ameliorate clinical response including patient's symptoms, the objective of scientific interest.This article covers recent developments in the area of cachexia and sarcopenia treatment and therapeutic interventions, targeting central nervous system involvement, key inflammatory and muscle-specific metabolic pathways.A number of promising agents have being evaluated, such as enobosarm, a selected androgen receptor modulator, and anamorelin, a ghrelin agonist which have been recently studied in phase III trials. These and other agents (i.e., infliximab, tocilizumab, MABp1, bimagrumab) have shown significant impact on reversal of skeletal muscle loss, but limited effect on physical function. In the last few years advancement in the number and type of potential treatments for cachexia and sarcopenia have been obtained and we have now available more data on measurable effects of several drugs on patients' nutritional and metabolic parameters and outcomes.

Background Muscle wasting, a prominent feature of cancer cachexia, is mainly caused by sustained protein hypercatabolism. The enhanced muscle protein degradation rates rely on the activity of different proteolytic systems, although the Adenosine triphosphate (ATP)‐ubiquitin‐proteasome‐dependent pathway and autophagy have been shown to play a pivotal role. Bortezomib is a potent reversible and selective proteasome and NF‐κB inhibitor approved for the clinical use, which has been shown to be effective in preventing muscle wasting in different catabolic conditions. The aim of the present study has been to investigate whether pharmacological inhibition of proteasome by bortezomib may prevent skeletal muscle wasting in experimental cancer cachexia.

Introduction Cachexia increases morbidity and mortality of cancer patients. The progressive loss of muscle mass negatively affects physical function and quality of life. We previously showed reduced muscle insulin-like growth factor-1 (IGF-1) expression and enhanced myostatin signaling in tumor-bearing animals. This study was aimed at investigating whether similar perturbations occur in gastric cancer patients. Methods Early perturbations of myostatin and IGF-1 signaling (including the expression of muscle-specific ubiquitin ligases) were investigated in 16 gastric cancer patients and in 6 controls by analyzing muscle mRNA expression with semiquantitative reverse transcriptase polymerase chain reaction (PCR) and real-time PCR. Results In gastric cancer patients, muscle mRNA levels for IGF-1, myostatin, and atrogin-1 were reduced irrespective of weight loss (≤5% or >5%), whereas MuRF1 expression was unchanged. Conclusions IGF-1 and myostatin mRNA levels are downregulated in gastric cancer patients who have minimal or no weight loss. These early alterations are particularly relevant in order to devise preventive and therapeutic strategies for cancer cachexia. Muscle Nerve 48: 387–392, 2013

Obesity represents a major under-recognized preventable risk factor for cancer development and recurrence, including breast cancer (BC). Healthy diet and correct lifestyle play crucial role for the treatment of obesity and for the prevention of BC. Obesity is significantly prevalent in western countries and it contributes to almost 50% of BC in older women. Mechanisms underlying obesity, such as inflammation and insulin resistance, are also involved in BC development. Fatty acids are among the most extensively studied dietary factors, whose changes appear to be closely related with BC risk. Alterations of specific ω-3 polyunsaturated fatty acids (PUFAs), particularly low basal docosahexaenoic acid (DHA) levels, appear to be important in increasing cancer risk and its relapse, influencing its progression and prognosis and affecting the response to treatments. On the other hand, DHA supplementation increases the response to anticancer therapies and reduces the undesired side effects of anticancer therapies. Experimental and clinical evidence shows that higher fish consumption or intake of DHA reduces BC cell growth and its relapse risk. Controversy exists on the potential anticancer effects of marine ω-3 PUFAs and especially DHA, and larger clinical trials appear mandatory to clarify these aspects. The present review article is aimed at exploring the capacity of DHA in controlling obesity-related inflammation and in reducing insulin resistance in BC development, progression, and response to therapies.

Basal rates of autophagy can be markedly accelerated by environmental stresses. Recently, autophagy has been involved in cancer-induced muscle wasting. Aim of this study has been to evaluate if autophagy is induced in the skeletal muscle of cancer patients. The expression (mRNA and protein) of autophagic markers has been evaluated in intraoperative muscle biopsies. Beclin-1 protein levels were increased in cachectic cancer patients, suggesting autophagy induction. LC3B-I protein levels were not significantly modified. LC3B-II protein levels were significantly increased in cachectic cancer patients suggesting either increased autophagosome formation or reduced autophagosome turnover. Conversely, p62 protein levels were increased in cachectic and non-cachectic cancer patients, suggesting impaired autophagosome clearance. As for mitophagy, both Bnip3 and Nix/Bnip3L show a trend to increase in cachectic patients. In the same patients, Parkin levels significantly increased, while PINK1 was unchanged. At gene level, Beclin-1, p-62, BNIP3, NIX/BNIP3L and TFEB mRNAs were not significantly modulated, while LC3B and PINK1 mRNA levels were increased and decreased, respectively, in cachectic cancer patients. Autophagy is induced in the skeletal muscle of cachectic cancer patients, although autophagosome clearance appears to be impaired. Further studies should evaluate whether modulation of autophagy could represent a relevant therapeutic strategy in cancer cachexia.

ObjectiveTo test the performance of appetite assessment tools among patients receiving hemodialysis (HD).DesignCross-sectional.SubjectsTwo hundred twenty-one patients receiving HD enrolled in seven dialysis facilities in Northern California.InterventionWe assessed 5 appetite assessment tools (self-assessment of appetite, subjective assessment of appetite, visual analog scale [VAS], Functional Assessment of Anorexia/Cachexia Therapy [FAACT] score, and the Anorexia Questionnaire [AQ]).Main outcome measuresReported food intake, normalized protein catabolic rate, and change in body weight were used as criterion measures, and we assessed associations among the appetite tools and biomarkers associated with nutrition and inflammation. Patients were asked to report their appetite and the percentage of food eaten (from 0% to 100%) during the last meal compared to usual intake.ResultsFifty-eight (26%) patients reported food intake ≤ 50% (defined as poor appetite). The prevalence of anorexia was 12% by self-assessment of appetite, 6% by subjective assessment of appetite, 24% by VAS, 17% by FAACT score, and 12% by AQ. All the tools were significantly associated with food intake ≤ 50% (P < .001), except self-assessment of appetite. The FAACT score and the VAS had the strongest association with food intake ≤ 50% (C-statistic 0.80 and 0.76). Patients with food intake ≤ 50% reported weight loss more frequently than patients without low intake (36% vs 22%) and weight gain less frequently (19% vs 35%; P = .03). Normalized protein catabolic rate was lower among anorexic patients based on the VAS (1.1 ± 0.3 vs 1.2 ± 0.3, P = .03). Ln interleukin-6 correlated inversely with food intake (P = .03), but neither interleukin-6 nor C-reactive protein correlated with any of the appetite tools. Furthermore, only the self-assessment of appetite was significantly associated with serum albumin (P = .02), prealbumin (P = .02) and adiponectin concentrations (P = .03).ConclusionsAlternative appetite assessment tools yielded widely different estimates of the prevalence of anorexia in HD. When considering self-reported food intake as the criterion standard for anorexia, the FAACT score and VAS discriminated patients reasonably well.

The growth hormone secretagogue receptor (GHS-R) is a component of the ghrelin signaling pathway and is involved in mediating the pleiotropic effects of ghrelin. Two isoforms have been identified, but only GHS-R1a binds with acyl ghrelin and transduces its message. However, the inactive variant of GHS-R, GHS-R1b, appears to play a critical role in modulating the activity of GHS-R1a by forming heterodimeric complexes which attenuates trafficking of the active variant to the cell surface. The molecular mechanisms of signal transduction are complex and are specific of the tissues where GHS-R1a is expressed. The potent induction of GH secretion and the stimulation of appetite are the most intensively studied functions of GHS-R1a. However, the tissue distribution of GHS-R1a extends beyond the pituitary and the hypothalamus, and reflects the different biological functions of the ghrelin/GHS-R system. GHS-R1a is also expressed in other brain areas, in the pancreas, adipose tissue, immune cells and cardiovascular system, and modulates learning and memory, glucose and lipid metabolism, inflammatory response and cardiac performance. The pleiotropic effects of the ghrelin/GHS-R system suggest their exploitation to prevent and treat a number of clinical conditions. Among many other syndromes and diseases, cancer cachexia, aging related cognitive decline, obesity and diabetes may significantly benefit from the use of GHS-R1a agonists or antagonists.

The management of cancer patients is frequently complicated by the occurrence of cachexia, a complex syndrome characterized by marked depletion of body weight, associated with profound alterations of both nutritional status and metabolic homeostasis. Progressive wasting of skeletal muscle mass and adipose tissue is a typical feature of cancer cachexia. This syndrome has a large impact on morbidity and mortality, and significantly affects patients’ quality of life. On this line, understanding the pathogenic mechanisms of cachexia is of crucial importance to define targeted therapeutic strategies. Many studies have addressed the relevance of nutritional interventions in cancer hosts. In particular, it has been shown that malnutrition in cancer patients can be delayed when nutritional supplementation is adopted early in the course of the disease. The preservation of a good nutritional status, in particular when it is achieved concurrently with specific antineoplastic treatment, will prevent or at least delay the onset of overt cachexia, allowing the use of more aggressive therapeutic regimens. This extended and updated version of our previously published article titled “ Nutritional support in cancer” will review the most recent and relevant literature, focusing on those options that have shown more promising for the clinical practice.

Increased cytokine expression contributes to the pathogenesis of cancer anorexia–cachexia syndrome. Carnitine may reduce inflammation in chronic diseases. We tested the effects of L-propionylcarnitine (PC group) or saline (C group) on food intake (FI), body composition, and inflammatory status of MCA-sarcoma-bearing rats. On tumor appearance, rats were randomly assigned to daily i.p. injection of L-propionylcarnitine (250 mg/kgBW/d; n = 8) or saline (equal volume; n = 8). FI and fat-free mass wasting improved in PC rats only (p < .01 vs. controls). Cytokines’ levels decreased in PC rats vs. controls (p < .02). Results suggest that carnitine may ameliorate cancer anorexia–cachexia, via reduction of the inflammatory status.

Cancer cachexia is a multifaceted syndrome characterized, among many symptoms, by extensive muscle wasting. Chronic systemic inflammation, partly triggered and sustained by cytokines, as well as increased oxidative stress contributes to the pathogenesis of this complex metabolic disorder. l-carnitine plays a central role in the metabolism of fatty acids and shows important antioxidant and anti-inflammatory properties. Systemic carnitine depletion has been described in several diseases, and it is characterized by fatigue, muscle weakness, and decreased tolerance to metabolic stress. In cachectic cancer patients, low serum carnitine levels have been reported, and this change has been suggested to play an important contributory role in the development of cachexia. Based on these data, carnitine supplementation has been tested in preliminary studies concerning human cachexia, resulting in improved fatigue and quality of life. We present here a review of clinical and experimental evidence regarding the use of carnitine supplementation in the management of cancer cachexia.

Cancer-associated malnutrition results from a deadly combination of anorexia, which leads to reduced food intake, and derangements of host metabolism inducing body weight loss, and hindering its reversal with nutrient supplementation. Cancer patients often experience both anorexia and weight loss, contributing to the onset of the clinical feature named as anorexia-cachexia syndrome. This condition has a negative impact upon patients' nutritional status. The pathogenesis of the anorexia-cachexia syndrome is multifactorial, and is related to: tumour-derived factors, host-derived factors inducing metabolic derangements, and side effects of anticancer therapies. In addition, the lack of awareness of cancer patients' nutritional issues and status by many oncologists, frequently results in progressive weight loss going undiagnosed until it becomes severe. The critical involvement of host inflammatory response in the development of weight loss, and, in particular, lean body mass depletion, limits the response to the provision of standard nutrition support. A novel nutritional and metabolic approach, named "parallel pathway", has been devised that may help maintain or improve nutritional status, and prevent or delay the onset of cancer cachexia. Such an approach may improve tolerance to aggressive anticancer therapies, and ameliorate the functional capacity and quality of life even in advanced disease stages. The "parallel pathway" implies a multiprofessional and multimodal approach aimed at ensuring early, appropriate and continuous nutritional and metabolic support to cancer patients in any phase of their cancer journey.

Over the past few years, medical care has dramatically improved knowledge of the pathogenic mechanisms of diseases, leading to more effective therapies as well as improved technologies, yielded to enhance survival for diseases that, just a few decades ago, would have been considered lethal. Unfortunately, not all diseases can be completely defeated. In many circumstances, therapies may delay the progression of the disease, leading to improved survival but bringing new issues to light. Of particular interest are nutritional and metabolic alterations due to both prolonged clinical course of disease and long-term therapies. Anorexia-cachexia syndrome often complicates the course of chronic illnesses. Anorexia (i.e., loss of appetite) and cachexia (i.e., loss of weight due to lean body mass and fat-mass wasting) are both associated with a number of diseases. The aim of this article is to highlight the clinical impact of the anorexia-cachexia syndrome and to review current and future etiologic therapeutic approaches.

Cancer anorexia frequently characterizes the clinical journey of patients with cancer and affects patients' morbidity, mortality, and quality of life. A constellation of symptoms concur to the diagnosis of anorexia, and early satiety, changes in taste/smell, and nausea are the more frequently reported. The pathogenesis of cancer anorexia is multifactorial, but accumulating evidence indicates that the hypothalamic melanocortin and neuropeptide Y systems become resistant to peripheral inputs. This results in increased melanocortin activity and reduced neuropeptide Y function, thereby leading to the promotion of catabolic stimuli (i.e., reduced energy intake, increased energy expenditure, possibly increased muscle proteolysis, and adipose tissue loss). Interestingly, hypothalamic proinflammatory cytokines and serotonin, among other factors, are key in triggering hypothalamic resistance. In the clinical setting, cancer anorexia develops with heterogeneous presenting symptoms (i.e., early satiety and/or nausea and/or changes of taste) and varying degrees of severity. Available evidence suggests that the constellation of symptoms characterizing this syndrome should be considered, at least in part, as different phenotypes of common neurochemical/metabolic alterations in the presence of a chronic inflammatory state.

Background: Anorexia is frequently found in end-stage renal disease and is a reliable predictor of morbidity and mortality in hemodialysis (HD) patients. The pathogenesis of anorexia is complex and the appetite-modulating hormone ghrelin could be involved. Two forms of circulating ghrelin have been described: acylated ghrelin (Methods: 34 HD patients and 15 healthy controls were studied. The presence of anorexia was assessed by a questionnaire. Serum des-acyl ghrelin was measured in HD patients and in 15 body mass index-, sex- and age-matched controls by ELISA. Energy intake was assessed by a 3-day dietary diary, and fat-free mass (FFM) was evaluated by body impedance analysis. Data have been statistically analyzed and are presented as mean ± SD. Results: 14 patients (41%) were found to be anorexic, and 20 patients (59%) non-anorexic. Energy intake (kcal/day) was significantly lower in anorexic than in non-anorexic patients (1,682 ± 241 vs. 1,972.50 ± 490; p < 0.05). FFM (%) was lower in anorexic than in non-anorexic patients (65.8 ± 4.4 vs. 70.9 ± 8.7; p = 0.05). Plasma des-acyl ghrelin levels (fmol/ml) were significantly higher in HD patients than in controls (214.88 ± 154.24 vs. 128.93 ± 51.07; p < 0.05), and in anorexic HD patients than in non-anorexic (301.7 ± 162.4 vs. 159.1 ± 115.5; p < 0.01). Conclusion: Anorexia is highly prevalent among HD patients and des-acyl ghrelin could be involved in its pathogenesis.

Inflammation characterizes the course of acute and chronic diseases and is largely responsible for the metabolic and behavioral changes occurring during the clinical journey of patients. Robust data indicate that, during cancer, functional modifications within brain areas regulating energy homeostasis contribute to the onset of anorexia, reduced food intake, and increased catabolism of muscle mass and adipose tissue. In particular, functional changes are associated with increased hypothalamic concentration of proinflammatory cytokines, which suggests that neuroinflammation may represent the adaptive response of the brain to peripheral challenges, including tumor growth. Within this conceptual framework, the vagus nerve appears to be involved in conveying alert signals to the hypothalamus, whereas hypothalamic serotonin appears to contribute to triggering catabolic signals.

Tumor growth is associated with profound metabolic and neurochemical alterations, which can lead to the onset of anorexia-cachexia syndrome. Anorexia is defined as the loss of the desire to eat, while cachexia results from progressive wasting of skeletal muscle mass--and to a lesser extent adipose tissue--occurring even before weight loss becomes apparent. Cancer anorexia-cachexia syndrome is highly prevalent among cancer patients, has a large impact on morbidity and mortality, and impinges on patient quality of life. However, its clinical relevance is frequently overlooked, and treatments are usually only attempted during advanced stages of the disease. The pathogenic mechanisms of cachexia and anorexia are multifactorial, but cytokines and tumor-derived factors have a significant role, thereby representing a suitable therapeutic target. Energy expenditure in anorexia is frequently increased while energy intake is decreased, which further exacerbates the progressive deterioration of nutritional status. The optimal therapeutic approach to anorectic-cachectic cancer patients should be based on both changes in dietary habits, achieved via nutritional counseling; and drug therapy, aimed at interfering with cytokine expression or activity. Our improved understanding of the influence a tumor has on the host's metabolism is advancing new therapeutic approaches, which are likely to result in better preservation of nutritional status if started concurrently with specific antineoplastic treatment.

The aim of the present review is to provide insights into the future therapeutic approaches to cancer-related muscle wasting that flow from the progressive knowledge of mechanisms regulating muscle mass in health and disease.Cancer cachexia is a severely debilitating and life-threatening paraneoplastic syndrome accounting for approximately 20% of cancer deaths. The prominent clinical feature of cancer cachexia is the progressive loss of muscle mass, which is substantially not reversible with any of the currently available nutritional, metabolic or pharmacological approaches. Cancer cachexia has long been considered a late event in the natural history of cancer patients, thus condemning them to merely palliative interventions. The accumulating evidence that the metabolic and molecular derangements ultimately leading to muscle wasting are operating early after tumour onset, even when weight loss is minimal or absent, is strengthening the view that cancer cachexia should be considered an early phenomenon.Currently, despite scientific and economic efforts, the therapy of cancer-related muscle wasting has a poor success rate. Present knowledge of the intracellular mechanisms involved in muscle homeoastasis is prompting continuous research aimed at developing more effective and selective therapeutic tools for the prevention and treatment of muscle loss in cancer.

Loss of lean body mass is commonly observed in cancer as well in other catabolic conditions such as sepsis, burns, severe injury, and renal failure. The progressive muscle wasting may have a negative impact on both the quality of life and the tolerance to antineoplastic therapies, accounting for one to two thirds of deaths in cancer patients. 1,2 Muscle depletion reflects an imbalance between the rates of protein synthesis and breakdown. Studies performed in experimental models as well as in human cancer have shown that muscle atrophy may result from increased degradation, reduced synthesis, or both. However, hypercatabolism of muscle protein is a frequent feature, while changes in protein synthesis seem to occur less frequently. 3 Intracellular protein degradation in the skeletal muscle depends on several proteolytic systems: the acidic lysosomal pathway, the calcium-dependent pathway, and the ATP-ubiquitin-dependent pathway. 4 The role played by the lysosomal and the calcium-dependent systems in the onset of muscle protein hypercatabolism does not seem to be crucial. Recently, however, calcium-dependent proteases have been proposed to be required for the initial degradation of myofibrillar proteins 5 and have been found to be activated in the skeletal muscle of tumor-bearing rats. 6 Upregulation of components of the ATP-ubiquitin-dependent pathway has been reported in experimental models of sepsis, trauma, burns, renal failure, acidosis, and cancer. 7–14 Overexpression of ubiquitin mRNA closely parallels the enhancement of protein degradation in the skeletal muscle of rats bearing the Yoshida AH-130 ascites hepatoma. 11 Moreover, treatment of the AH-130 hosts with agents able to block the onset of tissue protein hypercatabolism, such as anti-TNF antibodies or clenbuterol, also reduces muscle ubiquitin mRNA levels. 12,14 Modulations of the ubiquitin-proteasome pathway have been also documented in patients suffering from sepsis, trauma, AIDS, and cancer. 14–17 The ATP-ubiquitin-dependent proteolysis involves an enzymatic cascade by which multiple ubiquitin molecules are covalently attached to the protein substrate, which is then degraded by the 26S proteasome complex. The catalytic core of the 26S proteasome is the 20S proteasome, characterized by five peptidase activities: the trypsin-like (TL), chymotrypsin-like (CTL), peptidyl-glutamyl peptidase (PGP), branched-chain amino acid- preferring, and small neutral amino acid-preferring activities. 18 The aim of the present study was to investigate the state of activation of the ATP-ubiquitin-dependent proteolytic system in the skeletal muscle of gastric cancer patients. The results show that the cleavage of specific fluorogenic substrates is increased in the muscle of cancer patients with respect to controls, indicating that proteasome proteolytic activity is significantly enhanced in cancer hosts.

During sepsis, catabolism of proteins and associated changes in plasma amino acids occur. Tryptophan and tyrosine, and their derivatives serotonin (5-HT) and dopamine (DA), influence hypothalamic feeding-related areas and are associated with the onset of anorexia. We hypothesized that anorexia of sepsis is associated with changes in serotonin and dopamine in the ventromedial nucleus (VMN) of the hypothalamus. The aim of this study was to test our hypothesis by measuring intra-VMN changes of these two neurotransmitters at the onset of anorexia during sepsis. Fischer 344 male rats had an intracerebral guide cannula stereotaxically implanted into the VMN. Ten days later, in awake, overnight-food-deprived rats, a microdialysis probe was inserted through the in situ VMN cannula. Two hours thereafter, serial baseline serotonin and dopamine concentrations were measured. Then cecal ligation and puncture to induce sepsis or a control laparotomy was performed under isoflurane anesthesia. VMN microdialysis samples were serially collected every 30 min for 8 h after the surgical procedure to determine 5-HT and DA changes in response to sepsis. During the hypermetabolic response to sepsis, a strong association occurred between anorexia and a significant reduction of VMN dopamine concentration (P < 0.05; constant rate of dopamine decrease in the Study group of 0.99 pg per 2 h); no changes occurred in 5-HT in association with anorexia of sepsis. Six hours after operation, a single meal was offered for 20 min to assess the response of neurotransmitters to food ingestion. Food intake was minimal in anorectic septic rats (mean size of the after food-deprived meal in the Septic group was 0.03 ± 0.01 g, that of the Control group was 1.27 ± 0.14 g; P = 0.0001), while Control rats demonstrated anticipated changes in neurotransmitters in response to eating. We conclude that the onset of anorexia in septic rats is associated with a reduction in VMN dopamine.

With progression of tumor growth, rats demonstrate anorexia and reduced food intake, a function of meal number and meal size. Tumor necrosis factor-α (TNF-α), a recognized anorectic agent, reacts with two different receptors (type I: 55 kDa; type II: 75 kDa). We used a dimeric, pegylated 55-kDa TNF receptor construct to test its effects on food intake, meal number, and meal size, which were continuously measured with a rat eater meter in 16 Fischer 344 male rats injected with 106 viable methylcholanthrene cells. When anorexia developed, rats received a subcutaneous injection of either 0.25 mg/kg body wt of soluble TNF receptor construct (study) or vehicle (tumor-bearing control). Before TNF inhibitor injection, no differences were observed in food intake, meal number, or meal size between the two groups. After the TNF inhibitor injection, study vs. control rats significantly improved food intake as a result of an increase in meal number and meal size. Rats also showed a significant improvement in body weight. These data suggest that TNF-α, in addition to other cytokines, contributes to the anorexia of tumor growth, probably mediated via the hypothalamus.

OBJECTIVE: In obese patients, brain serotonergic stimulation via orally administered 5-hydroxy-tryptophan (5-HTP), the precursor of serotonin, causes decreased carbohydrate intake and weight loss. Since diabetes mellitus is associated with depressed brain serotonin, hyperphagia and carbohydrate craving, we hypothesized that in diabetic patients, orally administered 5-HTP stimulates brain serotonergic activity and thus normalizes eating behaviour. To test this hypothesis, we investigated whether in diabetic patients: 1) predicted brain serotonin concentrations are depressed as a result of decreased availability of the precursor, tryptophan; and 2) oral 5-HTP is effective in reducing energy and carbohydrate intake. SUBJECTS AND METHODS: 25 overweight non-insulin dependent diabetic outpatients were enrolled in a double-blind, placebo-controlled study, and randomized to receive either 5-HTP (750 mg/d) or placebo for two consecutive weeks, during which no dietary restriction was prescribed. Energy intake and eating behaviour, as expressed by macronutrient selection, were evaluated using a daily diet diary. Plasma amino acid concentrations and body weight, as well as serum glucose, insulin and glycosylated haemoglobin were assessed. RESULTS: 20 patients (nine from the 5-HTP group and 11 from the Placebo group) completed the study. Brain tryptophan availability in diabetic patients was significantly reduced when compared to a group of healthy controls. Patients receiving 5-HTP significantly decreased their daily energy intake, by reducing carbohydrate and fat intake, and reduced their body weight. CONCLUSIONS: These data confirm the role of the serotonergic system in reducing energy intake, by predominantly inhibiting carbohydrate intake, and suggest that 5-HTP may be safely utilized to improve the compliance to dietary prescriptions in non-insulin dependent diabetes mellitus.

Increased oxidative stress may contribute to cancer anorexia, which could be ameliorated by antioxidant supplementation. methylcholanthrene (MCA) sarcoma-bearing Fisher rats were studied. After tumour inoculation, rats were randomly assigned to standard diet (CTR group, n = 6), or to an antioxidant-enriched diet (AOX group, n = 8). Eight more rats (STD-AOX group) switched from standard to antioxidant diet when anorexia developed. At the end of the study, food intake (FI, g/d), body weight and tumour weight (g) were recorded, and plasma samples were obtained. On day 16, anorexia has appeared only in CTR and STD-AOX animals. At the end of the study, FI in AOX animals was still higher than in the other groups (p = 0.08). No differences in body and tumour weights were observed among groups. However, hydrogen peroxide and interleukin-1β levels were significantly reduced only in AOX rats. Data obtained suggest that early antioxidant supplementation improves cancer anorexia, ameliorates oxidative stress and reduces inflammation.

Background: Chronic diseases, including cirrhosis, are often accompanied by protein-energy malnutrition and muscle loss, which in turn negatively affect quality of life, morbidity and mortality. Unlike other chronic conditions, few data are available on the molecular mechanisms underlying muscle wasting in this clinical setting. Aims: To assess mechanisms of muscle atrophy in patients with cirrhosis. Methods: Nutritional [subjective global assessment (SGA) and anthropometry] and metabolic assessment was performed in 30 cirrhotic patients awaiting liver transplantation. Rectus abdominis biopsies were obtained intraoperatively in 22 cirrhotic patients and in 10 well-nourished subjects undergoing elective surgery for non-neoplastic disease, as a control group. Total RNA was extracted and mRNA for atrogenes (MuRF-1, Atrogin-1/MAFbx), myostatin (MSTN), GSK3b and IGF-1 was assayed. Results: A total of 50% of cirrhotic patients were malnourished based on SGA, while 53% were muscle-depleted according to mid-arm muscle area (MAMA

Whether in tumor-bearing rats a temporal relationship exists between an increase in plasma free tryptophan (FTRP), an increase in brain serotonin (5-HT), and onset of anorexia was studied. Rats were assigned to three groups: tumor-bearing (TB), pair fed (PF), and controls. Food intake was recorded daily. In TB rats anorexia developed on Day 18 and thereafter food intake decreased progressively until end of study. After tumor inoculation, tumor became palpable on Day 10 and continued to grow exponentially until end of study. Rats were killed on Days 6, 10, 16, 18, 22, and 26 to determine plasma FTRP, FTRP/LNAA, and brain 5-HT and compared to PF and controls. On Day 6, before tumors became detectable, FTRP and FTRP/LNAA were increased (P< 0.05) in TB rats vs controls. Both continued to increase so that by Day 18 when food intake had started to decrease (P< 0.05), brain 5-HT increased and correlated with the onset of anorexia (R2= 0.6,P< 0.05). Increases in plasma FTRP the precursor to brain 5-HT occurred in TB rats before physical appearance of tumor and increased until an increase in brain 5-HT occurred, leading to anorexia.

During tumor growth, anorexia and reduced food intake markedly contribute to the development of malnutrition, thusworsening overall patients' survival. A better understanding of the pathophysiology of eating behavior may lead to new and more effective therapies, aiming at counteracting the detrimental effects of anorexia and reduced food intake on nutritional status and survival in cancer patients. Brain tryptophan and serotonin concentrations seem to play a pivotal role in the regulation of eating behavior. Increased brain serotonin activity is indeed associated with a reduction of food intake. It has been recently hypothesized that increased availability of tryptophan to the brain and the consequent increased serotonin activity may represent the pathogenic mechanism for cancer-associated anorexia. According to this hypothesis, the modulation of brain serotonin activity may result in an improvement of anorexia. Reducing brain tryptophan availability represents a possible mechanism to restore brain serotonin activity to normal. There is evidence that the oral administration of neutral amino acids competing with tryptophan for brain entry results in a significant improvement of cancer anorexia. The same treatment may also be effective in improving secondary anorexia, which is associated with other chronic illnesses, including renal and liver failure, sepsis, and so forth, sharing a similar pathogenic mechanism.

SummaryResveratrol has been reported to improve metabolic function in metabolically abnormal rodents and humans, but it has not been studied in nonobese people with normal glucose tolerance. We conducted a randomized, double-blind, placebo-controlled trial to evaluate the metabolic effects of 12 weeks of resveratrol supplementation (75 mg/day) in nonobese, postmenopausal women with normal glucose tolerance. Although resveratrol supplementation increased plasma resveratrol concentration, it did not change body composition, resting metabolic rate, plasma lipids, or inflammatory markers. A two-stage hyperinsulinemic-euglycemic clamp procedure, in conjunction with stable isotopically labeled tracer infusions, demonstrated that resveratrol did not increase liver, skeletal muscle, or adipose tissue insulin sensitivity. Consistent with the absence of in vivo metabolic effects, resveratrol did not affect its putative molecular targets, including AMPK, SIRT1, NAMPT, and PPARGC1A, in either skeletal muscle or adipose tissue. These findings demonstrate that resveratrol supplementation does not have beneficial metabolic effects in nonobese, postmenopausal women with normal glucose tolerance.

High levels of glucocorticoids result in muscle wasting and weakness. β-hydroxy-β-methylbutyrate (HMB) attenuates the loss of muscle mass in various catabolic conditions but the influence of HMB on glucocorticoid-induced muscle atrophy is not known. We tested the hypothesis that HMB prevents dexamethasone-induced atrophy in cultured myotubes. Treatment of cultured L6 myotubes with dexamethasone resulted in increased protein degradation and expression of atrogin-1 and MuRF1, decreased protein synthesis and reduced myotube size. All of these effects of dexamethasone were attenuated by HMB. Additional experiments provided evidence that the inhibitory effects of HMB on dexamethasone-induced increase in protein degradation and decrease in protein synthesis were regulated by p38/MAPK- and PI3K/Akt-dependent cell signaling, respectively. The present results suggest that glucocorticoid-induced muscle wasting can be prevented by HMB.

The clinical journey of cancer patients is frequently complicated by the development of a complex and multifaceted syndrome, the main features of which are reduced appetite, decreased food intake, progressive weight loss, and wasting of muscle mass and adipose tissue, which is not prevented by the provision of calories and proteins. This syndrome, termed Cachexia, is responsible for increased morbidity, reduced survival, and impinged quality of life of cancer patients. The pathogenesis is complex and involves deranged metabolism of peripheral tissues and profound alterations of brain neurochemistry. Recent studies indicate that brain neurochemistry is perturbed during tumor growth by cancer-induced increased intrahypothalamic expression of proinflammatory cytokines. The attending neurochemical chaos mediates the anorexigenic behavioral responses associated to cancer cachexia, but recent data seem to suggest that neuronal output also may be involved in the metabolic changes occurring at the peripheral level.

Cancer cachexia is a disabling syndrome because of the complex interactions between the tumor, host metabolism, and proinflammatory cytokines that increases patients' morbidity and mortality. Considering the recent new definition and classification of cachexia, we aimed to review cancer cachexia from its underlying mechanisms to the clinical approach. Cancer cachexia is featured by a disruption in energy balance, metabolic changes, a decrease in fat mass, depletion of skeletal muscle mass, and perturbations in proinflammatory cytokines. Diagnostic effort should be focused on the recognition of precachexia to prevent or delay changes in body composition and nutritional complications secondary to cancer. From the point of disease diagnosis, every cancer patient needs continuous monitoring to receive effective, tailored nutritional and metabolic support. To date, practical guidelines to counteract cancer-related muscle wasting are lacking, mainly because of the multifactorial pathogenesis of the syndrome. A single therapy may not be effective; only a multimodal approach involving different treatment combinations is more likely to be successful in the prevention and treatment of cancer cachexia.

Cancer cachexia causes metabolic alterations with a marked effect on hepatic lipid metabolism. L-Car- nitine modulates lipid metabolism and its supplementation has been proposed as a therapeutic strategy in many dis- eases. In the present study, the effects of L-carnitine sup- plementation on gene expression and on liver lipid metabolism-related proteins was investigated in cachectic tumour-bearing rats. Wistar rats were assigned to receive 1 g/kg of L-carnitine or saline. After 14 days, supple- mented and control animals were assigned to a control (N), control supplemented with L-carnitine (CN), tumour-bear- ing Walker 256 carcinosarcoma (TB) and tumour-bearing supplemented with L-carnitine (CTB) group. The mRNA expression of carnitine palmitoyltransferase I and II (CPT I and II), microsomal triglyceride transfer protein (MTP), liver fatty acid-binding protein (L-FABP), fatty acid translocase (FAT/CD36), peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and organic cation trans- porter 2 (OCTN2) was assessed, and the maximal activity of CPT I and II in the liver measured, along with plasma and liver triacylglycerol content. The gene expression of MTP, and CPT I catalytic activity were reduced in TB, who also showed increased liver (150%) and plasma (3.3-fold) triacylglycerol content. L-Carnitine supplementation was able to restore these parameters back to control values (p \ 0.05). These data show that L-carnitine preserves hepatic lipid metabolism in tumour-bearing animals, sug- gesting its supplementation to be of potential interest in cachexia.

β-hydroxy-β-methylbutyrate (HMB), a leucine metabolite, improves muscle mass and function. This study aimed at evaluating the effects of HMB administration in an experimental in vivo model of cancer cachexia (CC). Wistar rats were randomized to receive standard or 4% HMB-enriched chow. Rats from both groups were randomized to receive an i.p. inoculum of AH-130 cells (TB). All rats were weighed and sacrificed at day 24. Liver, heart and muscles were dissected and weighed. The protein levels of p-p70S6k, p-eIf2α, p-mTOR and p-4-EB-P1 were evaluated by Western blotting on gastrocnemius muscle (GSN). As expected, the growth of the AH-130 ascites hepatoma induced significant carcass weight and GSN muscle loss. HMB treatment significantly increased GSN and heart weight in controls (p=0.002 and p

Inflammation contributes to the pathogenesis of cancer anorexia-cachexia syndrome. Nicotine administration reduces cytokine levels and mortality during sepsis. Therefore, nicotine administration may result in improved anorexia-cachexia. Sixteen male Fischer rats inoculated with MCA sarcoma were assigned to random injections of nicotine (NIC; 200 mg/kg BW/d) or saline (C). Food intake (FI), body weight, body composition, interleukin (IL)-1, IL-6 levels were evaluated. Data were analyzed via Student's t-test for paired and unpaired data and ANOVA. FI started declining 12 days after tumor inoculation both in C and NIC rats, but the decline was significantly attenuated by nicotine administration. At the end of the study, lean body mass wasting was more severe in C rats than in NIC rats (P

Aim We tested the effects of a cancer cachexia-anorexia sydrome upon the balance of anti and pro-inflammatory cytokines in the hypothalamus of sedentary or trained tumour-bearing (Walker-256 carcinosarcoma) rats. Methods Animals were randomly assigned to a sedentary control (SC), sedentary tumour-bearing (ST), and sedentary pair-fed (SPF) groups or, exercised control (EC), exercised tumour-bearing (ET) and exercised pair-fed (EPF) groups. Trained rats ran on a treadmill (60%VO2max) for 60 min/d, 5 days/wk, for 8 wks. We evaluated food intake, leptin and cytokine (TNF-α, IL1β) levels in the hypothalamus. Results The cumulative food intake and serum leptin concentration were reduced in ST compared to SC. Leptin gene expression in the retroperitoneal adipose tissue (RPAT) was increased in SPF in comparison with SC and ST, and in the mesenteric adipose tissue (MEAT) the same parameter was decreased in ST in relation to SC. Leptin levels in RPAT and MEAT were decreased in ST, when compared with SC. Exercise training was also able to reduce tumour weight when compared to ST group. In the hypothalamus, IL-1β and IL-10 gene expression was higher in ST than in SC and SPF. Cytokine concentration in hypothalamus was higher in ST (TNF-α and IL-1β, p < 0.05), compared with SC and SPF. These pro-inflammatory cytokines concentrations were restored to control values (p < 0.05), when the animals were submitted to endurance training. Conclusion Cancer-induced anorexia leads towards a pro-inflammatory state in the hypothalamus, which is prevented by endurance training which induces an anti-inflammatory state, with concomitant decrease of tumour weight.

Myostatin is a negative regulator of skeletal muscle mass. We recently demonstrated that myostatin expression is upregulated in an experimental model of cancer cachexia, suggesting that modulations of this pathway might play a pathogenic role in cancer-related muscle wasting. The present study was designed to investigate whether myostatin signaling is modulated in the muscle of non-weight-losing (nWL) patients with lung and gastric cancer. Myostatin signaling was studied in muscle biopsies obtained during surgical procedure from nWL patients affected by gastric (n = 16) or lung (n = 17) cancer. Western blotting was applied to test both the total expression of myostatin and the expression of phosphorylated form of GSK-3beta and Smad2/3. In patients with gastric cancer, the expression of both myostatin and phosphorylated GSK-3beta (p-GSK3β) were significantly increased. By contrast, in patients with lung cancer, myostatin levels were comparable to controls, whereas the expression of p-GSK3β significantly decreased in patients with disease stage III/IV. Myostatin signaling is altered in nWL cancer patients. Different tumor types may give rise to different patterns of molecular changes within the muscle, which occur even before cachexia becomes clinically apparent.

Reduced circulating and tissue carnitine levels, possibly leading to impaired mitochondrial function, have been postulated to be involved in the pathogenesis of insulin resistance. However, whether L-carnitine administration may improve insulin sensitivity in patients with impaired fasting glucose (IFG) or type 2 diabetes mellitus (DM-2) is still controversial. The aim of the study was to explore the role of L-carnitine supplementation in influencing insulin sensitivity.A randomized controlled study involving adult outpatients was designed. Adult patients referred to the outpatient clinic and within 10 days of the diagnosis of IFG or DM-2 were consecutively enrolled. Exclusion criteria were concomitant antidiabetic therapy and modifications of lifestyle during the previous 4 weeks. Patients were randomly assigned to receive a hypocaloric diet for 10 days (group C; n = 8) or the same dietetic regimen in addition to oral L-carnitine (2 g twice daily) supplementation (group LC; n = 8). Oral glucose tolerance test (OGTT), fasting plasma insulin levels, and homeostasis model assessment of insulin resistance (HOMA-IR) were assessed at the beginning and end of the study. Data were statistically analyzed using the Student t test for paired and unpaired data.OGTT at 2 hours improved in both groups. Only in the L-carnitine-supplemented group did plasma insulin levels and HOMA-IR significantly decrease when compared to baseline values.Considering the role of caloric restriction in increasing the intestinal uptake of carnitine, the results suggest that oral L-carnitine administration, when associated with a hypocaloric feeding regimen, improves insulin resistance and may represent an adjunctive treatment for IFG and DM-2.

Purpose of review Wasting diseases are characterized by progressive deterioration of nutritional status that negatively influences patients' outcome. The better understanding of the pathogenic mechanisms of wasting may lead to effective therapies. Tryptophan metabolism has unique features suggesting a critical role in influencing human metabolism under normal and pathological conditions. Recent findings During disease, inflammatory response favours the local depletion of the essential amino acid tryptophan, thereby inhibiting cellular proliferation. Tryptophan depletion may also mediate immunotolerance to foreign antigens. In contrast, brain accumulation of tryptophan contributes to wasting by increasing oxidative stress and hypothalamic serotonin neurotransmission, and thereby triggering the onset of sickness behaviour followed by depressive-like behaviour. Summary Tryptophan metabolism is critical in mediating a number of important biological responses. Restoring tryptophan metabolism may well result in enhanced recovery from disease.

Impairment of the nutritional state plays a major role in the morbidity and mortality of cancer patients. However, the opportunity of providing artificial nutritional support to these patients is still debated, because of the concern that energy substrates administered to replete the host may concomitantly stimulate tumor growth. A correct nutritional approach to cancer patients should thus be based on a thorough knowledge of both host and tumor metabolic needs and host-tumor metabolic interactions. Specific modifications of plasma levels of glucogenic, aromatic, sulfur-containing and branched-chain amino acids have been demonstrated in cancer patients, indicating a specific influence of the tumor on amino acid metabolism. Little is known about protein metabolism in neoplastic tissue. Interference with tumor growth has been attempted by deprivation of single amino acids with controversial results. Increased gluconeogenesis and insulin resistance are responsible for the two main abnormalities in carbohydrate metabolism in cancer patients, namely increased glucose turnover and impaired glucose tissue disposal. Lipid metabolism is also affected by the neoplasm: soluble factors such as "lipid-mobilizing factor" lead to increased fat mobilization from adipose tissue; plasma elimination of exogenous triglycerides has also been found to be reduced probably because of a tumor-related decrease in lipoprotein lipase activity. The differences in glucose and fat utilization between tumor and host should be considered in the nutritional approach to cancer patients. Data in this respect are controversial and have been obtained only in experimental animals.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of isocaloric carbohydrate-based vs. fat-based total parenteral nutrition (TPN) regimens on cancer cell proliferation and host nutritional status were evaluated in 27 patients with tumours of the gastro intestinal tract consecutively assigned to receive for 14 days: a glucose-based (A) or a lipid-based (B) TPN formula, or an oral diet (C) isocaloric and isonitrogenous to A and B. Cancer cell replication rate was evaluated by thymidine labelling index (LI) on tumour samples before and at the end of each nutritional regimen. The number of replicating cells increased by 32.2% in patients receiving regimen A. LI decreased by 24.3% in patients given regimen B. LI values were slightly increased (+15%) in patients maintained on regimen C. Nutritional status remained within normal limits. None of the LI changes observed between and within the three arms of the trial were found to be statistically significant. Thus we failed to prove that glucose consistently stimulates or lipids inhibit tumour proliferation despite a trend in this sense.

The anorexia-cachexia syndrome is a debilitating clinical condition characterizing the course of chronic diseases, which heavily impacts on patients' morbidity and quality of life, ultimately accelerating death. The pathogenesis is multifactorial and reflects the complexity and redundancy of the mechanisms controlling energy homeostasis under physiological conditions. Accumulating evidence indicates that, during disease, disturbances of the hypothalamic pathways controlling energy homeostasis occur, leading to profound metabolic changes in peripheral tissues. In particular, the hypothalamic melanocortin system does not respond appropriately to peripheral inputs, and its activity is diverted largely toward the promotion of catabolic stimuli (i.e., reduced energy intake, increased energy expenditure, possibly increased muscle proteolysis, and adipose tissue loss). Hypothalamic proinflammatory cytokines and serotonin, among other factors, are key in triggering hypothalamic resistance. These catabolic effects represent the central response to peripheral challenges (i.e., growing tumor, renal, cardiac failure, disrupted hepatic metabolism) that are likely sensed by the brain through the vagus nerve. Also, disease-induced changes in fatty acid oxidation within hypothalamic neurons may contribute to the dysfunction of the hypothalamic melanocortin system. Ultimately, sympathetic outflow mediates, at least in part, the metabolic changes in peripheral tissues. Other factors are likely involved in the pathogenesis of the anorexia-cachexia syndrome, and their role is currently being elucidated. However, available evidence shows that the constellation of symptoms characterizing this syndrome should be considered, at least in part, as different phenotypes of common neurochemical/metabolic alterations in the presence of a chronic inflammatory state.

On December 13th and 14th a group of scientists and clinicians met in Washington, DC, for the cachexia consensus conference. At the present time, there is no widely agreed upon operational definition of cachexia. The lack of a definition accepted by clinician and researchers has limited identification and treatment of cachectic patient as well as the development and approval of potential therapeutic agents. The definition that emerged is: "cachexia, is a complex metabolic syndrome associated with underlying illness and characterized by loss of muscle with or without loss of fat mass. The prominent clinical feature of cachexia is weight loss in adults (corrected for fluid retention) or growth failure in children (excluding endocrine disorders). Anorexia, inflammation, insulin resistance and increased muscle protein breakdown are frequently associated with cachexia. Cachexia is distinct from starvation, age-related loss of muscle mass, primary depression, malabsorption and hyperthyroidism and is associated with increased morbidity". While this definition has not been tested in epidemiological or intervention studies, a consensus operational definition provides an opportunity for increased research.

Cachexia is pervasive among patients suffering from chronic diseases, including cancer, liver cirrhosis and chronic renal failure. The development of cachexia dramatically impacts on the clinical course of the underlying disease, by increasing morbidity and mortality, and impinging on patients’ quality of life. Also, weight loss influences outcome by increasing drug-induced toxicity and impeding completion of the therapeutic schedule. Particularly in cancer patients, weight loss is a reliable predictor for toxicity from treatment and shorter survival [1].

Peripheral administration of interleukin-1 (IL-1) reduces food intake and affects brain serotonergic activity, suggesting a causal relationship. Furthermore, IL-1 increases the brain concentrations of the serotonin precursor, tryptophan (TRP), by unclear mechanism(s). We aimed at confirming the link between IL-1 administration, raised brain TRP concentrations and the development of anorexia, and at investigating the mechanisms of TRP entry into the brain. Thirty adult, overnight fasted Sprague-Dawley rats were randomly assigned to i.p. injections of 1 mug/kg BW of IL-1 alpha (n=10) or vehicle (n=10), or to pair-feeding with IL-1 animals (n=10). After 2 h, food intake, blood plasma concentrations of total TRP, free TRP, large neutral amino acids (LNAA; competing with TRP for brain entry) were measured. Cerebral spinal fluid (CSF) TRP concentrations were also measured. TRP brain availability was assessed by calculating the plasma ratio free TRP/LNAA. Following IL-1 injection, food intake significantly declined in IL-1 rats, which was paralleled by decreased plasma free TRP and increased plasma LNAA. Despite a decrease in the free TRP/LNAA ratios in plasma, IL-1 significantly increased concentrations of TRP in CSF. These data show that the acute peripheral administration of IL-1 induces anorexia and raises CSF TRP levels. Considering the possible role of the raised CSF TRP in influencing brain serotonin activity, it is postulated that increased serotonergic neurotransmission could be involved in IL-1 induced anorexia.

Cancer anorexia-cachexia syndrome is becoming a critical component in the comprehensive approach to cancer patients because it influences morbidity, mortality and quality of life. Consequently, pathogenic mechanisms have been elucidated to facilitate development of better therapies. Reported findings indicate that increased production of reactive oxygen species and reduced activity of antioxidant enzymes contribute to development of anorexia and cachexia in cancer.Systemic inflammation impairs tryptophan handling, promoting oxidative stress, which appears to mimic hypothalamic negative feedback signalling. Thus, tryptophan contributes to cancer anorexia by stimulating hypothalamic serotonergic activity and promoting oxidative stress, because neuroinflammation facilitates tryptophan degradation into free radical generators via the kynurenine pathway. Upregulation of protein degradation by increased oxidative stress has been documented in cancer. Also, hypothalamic, cytokine-mediated suppression of fatty acid oxidation reduces food intake, and triggers mitochondrial biogenesis and oxidative gene expression in skeletal muscle, thus potentially increasing oxidative stress.Increased oxidative stress contributes to cancer anorexia and cachexia. Preliminary clinical data on the efficacy of antioxidant therapy in cancer patients are encouraging, but uncertainty persists regarding the optimal dose and timing of administration. Also, better biological/genetic characterization of those cancer patients who are more likely to obtain significant clinical benefits appears necessary.

Purpose of review The clinical course of most chronic diseases is associated with declined energy intake and nutrient-resistant progressive myopathy, characterized by accelerated proteolysis and impaired function. This anorexia/cachexia syndrome leads to deterioration of quality of life, and increased morbidity and mortality. The clinical efficacy of currently available therapeutic strategies is limited and more effective treatments are needed. Recent findings Chronic systemic inflammation, triggered and sustained by cytokines, and increased oxidative stress contribute to the pathogenesis of the anorexia/cachexia syndrome. Carnitine and nicotine have recently been tested as immunomodulating and antioxidant agents. In particular, carnitine supplementation has been shown to reduce chronic inflammation and oxidative stress in hemodialysis patients and, in cancer patients, yielding to reduced fatigue and improved outcome. Nicotine is able to induce the anti-inflammatory activity of the vagus nerve. In animal models of sepsis and cancer, the nicotine-induced supplementation resulted in better protection of nutritional status and improved survival. Summary In the continuous effort to develop more efficacious strategies against the anorexia/cachexia syndrome, carnitine and nicotine may represent a further therapeutic tool. More clinical studies are needed, however, before their use can be routinely suggested.

Cancer cachexia is characterized by skeletal muscle wasting that is mainly supported by hypercatabolism. Muscle atrophy has been suggested to depend on impaired IGF-1 signal transduction pathway. The present study has been aimed at investigating the IGF-1 system in rats bearing the AH-130 hepatoma, a well-characterized model of cachexia. IGF-1 mRNA expression in the gastrocnemius of tumor hosts progressively decreases to ∼50% of controls. By contrast, both IGF-1 receptor and insulin receptor mRNA levels increase in day 7 AH-130 hosts. IGF-1 and insulin circulating levels, as well as IGF-1 expression in the liver, are reduced. Muscle wasting in the AH-130 bearers is associated with hyperactivation of the ubiquitin-proteasome system. Consistently, the mRNA levels of ubiquitin and of the ubiquitin ligases atrogin-1 and MuRF1 are significantly increased in the gastrocnemius of day 7 AH-130 hosts. Exogenous IGF-1 administered to tumor bearers does not prevent cachexia. IGF-1 mRNA levels also have been evaluated in the gastrocnemius of AH-130 hosts treated with pentoxifylline, an inhibitor of TNF-α synthesis, alone or combined with formoterol, a β2-adrenergic agonist. Both treatments partially correct muscle atrophy without modifying IGF-1 and atrogin-1 mRNA levels, whereas MuRF1 hyperexpression is reduced by the combination of pentoxifylline with formoterol. These results demonstrate for the first time that the IGF-1 system is downregulated in cancer cachexia, although the underlying mechanism remains unknown. Moreover, no simple relation linking IGF-1 and/or atrogin-1 mRNA levels and muscle atrophy could be observed in these experimental conditions. Further studies are thus needed to clarify both issues.

Cancer cachexia (CC) is a multifactorial paraneoplastic syndrome characterized by anorexia, body weight loss, loss of adipose tissue and skeletal muscle, accounting for at least 20% of deaths in neoplastic patients. CC significantly impairs quality of life and response to anti-neoplastic therapies, increasing morbidity and mortality of cancer patients. Muscle wasting is the most important phenotypic feature of CC and the principal cause of function impairment, fatigue and respiratory complications, mainly related to a hyperactivation of muscle proteolytic pathways. Most therapeutic strategies to CC have proven to be only partially effective . The inhibition of catabolic processes in muscle has been attempted pharmacologically with encouraging results in animal models. However, data in the clinical setting are still scanty and contradictory. Stimulation of muscle anabolism could represent a promising and valid therapeutic alternative for cancer-related muscle wasting. This goal may be currently achieved with the conventional, short-acting and adverse side effect-rich anabolic steroids. Insulin-like growth factor-1 (IGF-1) plays a critical role in muscle homeostasis, hypertrophy and regeneration. IGF-1 overexpression at the muscular level by gene therapy reverses muscle hypotrophy secondary to catabolic conditions and induces muscle hypertrophy increasing muscle mass and strength. This allows the speculation that this approach could also prove effective in modulating cancer-induced muscle wasting, while avoiding the potentially hazardous side effects of systemic IGF-1 administration. The present review will focus on the potential biochemical and molecular targets of CC therapy, and will define the rationale for a novel, gene therapy-based approach.

Anatomy, Historical Perspective and Epidemiology.- Functional Anatomy of the 'Adipose Organ'.- Body Silhouette and Body Fat Distribution.- Historic Views on Cachexia in Humans with Special Reference to Cardiac Cachexia.- Epidemiology of Cachexia.- Biochemistry, Physiology and 'Clinics' of Adipose Tissue.- Energy Values of Foods.- Diet-Induced Thermogenesis.- Assessment of Nutritional Status.- Biochemical Parameters of Nutrition.- Nitrogen Balance and Protein Requirements: Definition and Measurements.- Plasma Proteins and Protein Catabolism.- Nutritional Status Assessment.- Immunological Parameters of Nutrition.- Functional Parameters of Nutrition.- The Different Features of Wasting in Humans.- Anorexia.- Starvation: Social, Voluntary, and Involuntary Causes of Weight Loss.- Cachexia Related to Multiple Causes.- Non-AIDS Lipodystrophy Syndrome.- Pathophysiology of Wasting/Cachexia.- Body Composition: Physiology, Pathophysiology and Methods of Evaluation.- Protein Metabolism in Cachexia.- Lipid Metabolism in Cachexia.- Glucose Metabolism.- Cytokines in Cachexia.- Cytokines in Chronic Inflammation.- Biochemistry of the Growth Hormone-Releasing Peptides, Secretagogues and Ghrelin.- Ghrelin as a New Factor in the Central Network Controlling Appetite and Food Intake.- Leptin and Des-acyl Ghrelin: Their Role in Physiological Body Weight Regulation and in the Pathological State.- Brain Mechanisms in Wasting and Cachexia.- Body Weight Regulation and Hypothalamic Neuropeptides.- Medical Causes of Wasting/Cachexia.- Diabetes.- Endocrine Disorders.- Psychiatric Diseases and Depression.- Cachexia in Chronic Kidney Disease: Malnutrition-Inflammation Complex and Reverse Epidemiology.- Gastrointestinal Diseases.- Chronic Obstructive Pulmonary Disease (COPD) and Treatment of COPD-Related Cachexia.- Cachexia in Cardiovascular Illness.- Cachexia and Ageing.- Epidemiology of Malnutrition in the Elderly.- Pathophysiology of Body Composition Changes in Elderly People.- The Pharmacokinetics and Pharmacodynamics of Drugs in Elderly Cachectic (Cancer) Patients.- Pathophysiology of Cachexia in the Elderly.- Cytokines and Disability in Older Adults.- Cachexia and HIV Infection/AIDS.- HIV Infection-Related Cachexia and Lipodystrophy.- Treatment of AIDS Anorexia-Cachexia Syndrome and Lipodystrophy.- Cancer-Related Cachexia.- Cancer Cachexia and Fat Metabolism.- The Role of Cytokines in Cancer Cachexia.- Proinflammatory Cytokines: Their Role in Multifactorial Cancer Cachexia.- Proteolysis-Inducing Factor in Cancer Cachexia.- Lipid Mobilising Factor in Cancer Cachexi.- Dietary Intake, Resting Energy Expenditure, Weight Loss, and Survival in Cancer Patients.- The Ubiquitin/Proteasome System in Cancer Cachexia.- Non-Gl-Malignancy-Related Malabsorption Leads to Malnutrition and Weight Loss.- Omega-3 Fatty Acids, Cancer Anorexia, and Hypothalamic Gene Expression.- The Role of Pineal Hormone Melatonin in Cancer Cachexia.- Eating-Related Distress of Patients with Advanced, Incurable Cancer and of Their Partners.- Challenges of Geriatric Oncology.- Treatment of Cancer Cachexia.- The Current Management of Cancer Cachexia.- The Role of Artificial Nutrition Support in the Cancer Patient.- The Role of Appetite Stimulants for Cancer-Related Weight Loss.- Palliative Management of Anorexia/Cachexia and Associated Symptoms.- Pharmaco-Nutritional Supports for the Treatment of Cancer Cachexia.- A Critical Assessment of the Outcome Measures and Goals of Intervention in Cancer Cachexia.- Meeting the Amino Acid Requirements for Protein Anabolism in Cancer Cachexia.- The Role of Branched-Chain Amino Acids and Serotonin Antagonists in the Prevention and Treatment of Cancer Cachexia.- An Update on Therapeutics: The Cancer Anorexia/Weight Loss Syndrome in Advanced Cancer Patients.- Medroxyprogesterone Acetate in Cancer Cachexia.- Progestagens and Corticosteroids in the Management Cancer Cachexia.- COX-2 Inhibitors in Cancer Cachexia.- Anti-TNF-? Antibody and Cancer Cachexia.- A Phase II Study with Antioxidants, both in the Diet and Supplemented, Pharmaco-Nutritional Support, Progestagen and Anti-COX-2 Showing Efficacy and Safety in Patients with Cancer-Related Anorexia-Cachexia and Oxidative Stress.- Treatment of Cachexia in the Elderly.- Treatment of Cachexia in the Elderly.- Treatment of Sarcopenia and Cachexia in the Elderly.- Management of Weight Loss in Older Persons.- A Global Perspective for the Treatment of Cachexia.- Cachexia: Therapeutic Immunomodulation Beyond Cytokine Antagonism.