Cardiac cachexia: a systematic overview

Molecular and cellular mechanisms of skeletal muscle atrophy: an update

Skeletal muscle atrophy is defined as a decrease in muscle mass and it occurs when protein degradation exceeds protein synthesis. Potential triggers of muscle wasting are long-term immobilization, malnutrition, severe burns, aging as well as various serious and often chronic diseases, such as chronic heart failure, obstructive lung disease, renal failure, AIDS, sepsis, immune disorders, cancer, and dystrophies. Interestingly, a cooperation between several pathophysiological factors, including inappropriately adapted anabolic (e.g., growth hormone, insulin-like growth factor 1) and catabolic proteins (e.g., tumor necrosis factor alpha, myostatin), may tip the balance towards muscle-specific protein degradation through activation of the proteasomal and autophagic systems or the apoptotic pathway. Based on the current literature, we present an overview of the molecular and cellular mechanisms that contribute to muscle wasting. We also focus on the multifacetted therapeutic approach that is currently employed to prevent the development of muscle wasting and to counteract its progression. This approach includes adequate nutritional support, implementation of exercise training, and possible pharmacological compounds.

An international model to predict recurrent cardiovascular disease

BACKGROUND

Prediction models for cardiovascular events and cardiovascular death in patients with established cardiovascular disease are not generally available.

METHODS

Participants from the prospective REduction of Atherothrombosis for Continued Health (REACH) Registry provided a global outpatient population with known cardiovascular disease at entry. Cardiovascular prediction models were estimated from the 2-year follow-up data of 49,689 participants from around the world.

RESULTS

A developmental prediction model was estimated from 33,419 randomly selected participants (2394 cardiovascular events with 1029 cardiovascular deaths) from the pool of 49,689. The number of vascular beds with clinical disease, diabetes, smoking, low body mass index, history of atrial fibrillation, cardiac failure, and history of cardiovascular event(s) <1 year before baseline examination increased risk of a subsequent cardiovascular event. Statin (hazard ratio 0.75; 95% confidence interval, 0.69-0.82) and acetylsalicylic acid therapy (hazard ratio 0.90; 95% confidence interval, 0.83-0.99) also were significantly associated with reduced risk of cardiovascular events. The prediction model was validated in the remaining 16,270 REACH subjects (1172 cardiovascular events, 494 cardiovascular deaths). Risk of cardiovascular death was similarly estimated with the same set of risk factors. Simple algorithms were developed for prediction of overall cardiovascular events and for cardiovascular death.

CONCLUSIONS

This study establishes and validates a risk model to predict secondary cardiovascular events and cardiovascular death in outpatients with established atherothrombotic disease. Traditional risk factors, burden of disease, lack of treatment, and geographic location all are related to an increased risk of subsequent cardiovascular morbidity and cardiovascular mortality.

Ghrelin improves body weight loss and skeletal muscle catabolism associated with angiotensin II-induced cachexia in mice

Ghrelin is a gastric peptide that regulates energy homeostasis. Angiotensin II (Ang II) is known to induce body weight loss and skeletal muscle catabolism through the ubiquitin-proteasome pathway. In this study, we investigated the effects of ghrelin on body weight and muscle catabolism in mice treated with Ang II. The continuous subcutaneous administration of Ang II to mice for 6 days resulted in cardiac hypertrophy and significant decreases in body weight gain, food intake, food efficiency, lean mass, and fat mass. In the gastrocnemius muscles of Ang II-treated mice, the levels of insulin-like growth factor 1 (IGF-1) were decreased, and the levels of mRNA expression of catabolic factors were increased. Although the repeated subcutaneous injections of ghrelin (1.0mg/kg, twice daily for 5 days) did not affect cardiac hypertrophy, they resulted in significant body weight gains and improved food efficiencies and tended to increase both lean and fat mass in Ang II-treated mice. Ghrelin also ameliorated the decreased IGF-1 levels and the increased mRNA expression levels of catabolic factors in the skeletal muscle. IGF-1 mRNA levels in the skeletal muscle significantly decreased 24h after Ang II infusion, and this was reversed by two subcutaneous injections of ghrelin. In C2C12-derived myocytes, the dexamethasone-induced mRNA expression of atrogin-1 was decreased by IGF-1 but not by ghrelin. In conclusion, we demonstrated that ghrelin improved body weight loss and skeletal muscle catabolism in mice treated with Ang II, possibly through the early restoration of IGF-1 mRNA in the skeletal muscle and the amelioration of nutritional status.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): cardiac patient]

Patients with cardiac disease can develop two types of malnutrition: cardiac cachexia, which appears in chronic congestive heart failure, and malnutrition due to the complications of cardiac surgery or any other type of surgery in patients with heart disease. Early enteral nutrition should be attempted if the oral route cannot be used. When cardiac function is severely compromised, enteral nutrition is feasible, but supplementation with parenteral nutrition is sometimes required. Sustained hyperglycemia in the first 24 hours in patients admitted for acute coronary syndrome, whether diabetic or not, is a poor prognostic factor for 30-day mortality. In critically-ill cardiac patients with stable hemodynamic failure, nutritional support of 20-25 kcal/kg/day is effective in maintaining adequate nutritional status. Protein intake should be 1.2*-1.5 g/kg/day. Routine polymeric or high protein formulae should be used, according to the patient's prior nutritional status, with sodium and volume restriction according to the patient's clinical situation. The major energy source for myocytes is glutamine, through conversion to glutamate, which also protects the myocardial cell from ischemia in critical situations. Administration of 1 g/ day of omega-3 (EPA+DHA) in the form of fish oil can prevent sudden death in the treatment of acute coronary syndrome and can also help to reduce hospital admission for cardiovascular events in patients with chronic heart failure.

High nutritional risk is associated with worse health-related quality of life in patients with heart failure beyond sodium intake

BACKGROUND

The most desirable outcome in heart failure (HF) management is to improve health-related quality of life (HRQoL) as a patient-centred health outcome. Nutrition is assumed to be important in HF management, whereas there is little evidence that nutritional risk affects HRQoL, except for sodium.

PURPOSE

We aimed to determine whether nutritional risk is associated with worse HRQoL after controlling for daily sodium intake.

METHODS

A total of 134 consecutive patients with HF [age 63 ± 11 years, 35% female, 45% New York Heart Association (NYHA) class III/IV, ejection fraction (EF) 33 ± 13%] completed the Nutrition Screening Initiative (NSI) to assess nutritional risk and a 24-h urine sodium excretion assessment to estimate daily sodium intake at baseline. The Minnesota Living with HF Questionnaire was used to evaluate HRQoL at baseline and 6 months later. Hierarchical linear regressions were used to determine whether nutritional risk predicted HRQoL at baseline and 6 months later.

RESULTS

Seventy-eight (58.2%) patients had high nutritional risk as indicated by a total NSI score ≥ 6. Increased nutritional risk was independently associated with worse HRQoL at baseline and 6 months later (β = 0.33, p < 0.001; β = 0.35, p < 0.001, respectively), after controlling for age, gender, aetiology, body mass index, NYHA class, EF, total comorbidity score, prescribed medications, and daily sodium intake.

CONCLUSION

These findings show that higher nutritional risk beyond sodium intake affects worse HRQoL in patients with HF. Further work is required to provide specific dietary guidelines to improve health outcomes for patients with HF.

Angiotensin II reduces food intake by altering orexigenic neuropeptide expression in the mouse hypothalamus

Angiotensin II (Ang II), which is elevated in many chronic disease states such as end-stage renal disease and congestive heart failure, induces cachexia and skeletal muscle wasting by increasing muscle protein breakdown and reducing food intake. Neurohormonal mechanisms that mediate Ang II-induced appetite suppression are unknown. Consequently, we examined the effect of Ang II on expression of genes regulating appetite. Systemic Ang II (1 μg/kg · min) infusion in FVB mice rapidly reduced hypothalamic expression of neuropeptide Y (Npy) and orexin and decreased food intake at 6 h compared with sham-infused controls but did not change peripheral leptin, ghrelin, adiponectin, glucagon-like peptide, peptide YY, or cholecystokinin levels. These effects were completely blocked by the Ang II type I receptor antagonist candesartan or deletion of Ang II type 1a receptor. Ang II markedly reduced phosphorylation of AMP-activated protein kinase (AMPK), an enzyme that is known to regulate Npy expression. Intracerebroventricular Ang II infusion (50 ng/kg · min) caused a reduction of food intake, and Ang II dose dependently reduced Npy and orexin expression in the hypothalamus cultured ex vivo. The reduction of Npy and orexin in hypothalamic cultures was completely prevented by candesartan or the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside. Thus, Ang II type 1a receptor-dependent Ang II signaling reduces food intake by suppressing the hypothalamic expression of Npy and orexin, likely via AMPK dephosphorylation. These findings have major implications for understanding mechanisms of cachexia in chronic disease states such as congestive heart failure and end-stage renal disease, in which the renin-angiotensin system is activated.

Growth hormone, insulin-like growth factor 1, and insulin signaling-a pharmacological target in body wasting and cachexia

Cachexia is an irreversible process that can develop in the course of chronic disease. It is characterized by the remodeling of the metabolic, inflammatory, and endocrine pathways. Insulin, growth hormone (GH), and insulin-like growth factor 1 (IGF-1) are involved in glucose, protein, and fat metabolism, which regulates body composition. In body wasting and cachexia, their signaling is impaired and causes anabolic/catabolic imbalance. Important mechanisms include inflammatory cytokines and neurohormonal activation. Remodeled post-receptor insulin, GH, and IGF-1 pathways constitute a potential target for pharmacological treatment in the setting of body wasting and cachexia. Peroxisome proliferator-activated receptor gamma agonists, drugs inhibiting angiotensin II action (angiotensin II antagonists and inhibitors of angiotensin-converting enzyme), and testosterone, which interfere with post-receptor pathways of insulin, GH, and IGF-1, were investigated as pharmacological intervention targets and various clinically important implications were reported. There are several other potential targets, but their treatment feasibility and applicability is yet to be established.

Cachexia and sarcopenia: emerging syndromes of importance in dogs and cats

Cachexia is the loss of lean body mass (LBM) that affects a large proportion of dogs and cats with congestive heart failure (CHF), chronic kidney disease (CKD), cancer, and a variety of other chronic diseases. Sarcopenia, the loss of LBM that occurs with aging, is a related syndrome, although sarcopenia occurs in the absence of disease. As many of the diseases associated with muscle loss are more common in aging, cachexia and sarcopenia often are concurrent problems. Both cachexia and sarcopenia have important clinical implications because they are associated with increased morbidity and mortality. The pathophysiology of these 2 syndromes is complex and multifactorial, but recent studies have provided new information that has helped to clarify mechanisms and identify potential new targets for treatment. Newly identified mechanisms and pathways that mediate cachexia appear to act by increasing energy requirements, decreasing energy intake, impairing nutrient absorption, and causing metabolic alterations. Whereas cachexia and sarcopenia are important areas of research for drug development in people, they are only beginning to be recognized in veterinary medicine. Greater awareness and earlier diagnosis will help provide practical approaches to managing body weight and lean tissue in dogs and cats, as well as more directed targets for treatment.

[Serum albumin and heart failure: recent advances on a new paradigm]

Hypoalbuminemia is a common condition in patients with heart failure and is mainly related to the malnutrition-inflammation complex syndrome. Other causal factors can be involved, which include hemodilution, liver dysfunction, increased transcapillary escape rate, renal and enteral loss. Evidence is growing that hypoalbuminemia independently predicts incident heart failure in patients with end-stage renal disease and elderly patients, as well as mortality in patients with heart failure regardless of left ventricular ejection fraction and clinical presentation. Hypoalbuminemia induces a low plasma oncotic pressure, which facilitates pulmonary edema in patients without critical increase in pulmonary capillary hydrostatic pressures. Hypoalbuminemia may also contribute to the progression of heart failure by favoring myocardial edema, volume overload, diuretic resistance and exacerbation of oxidative stress and inflammation. If relevant, removal of subclinical excess of fluid and renutrition may be indicated in patients with heart failure and hypoalbuminemia. Additional research is warranted to determine the specific role of serum albumin in the pathophysiologic process of heart failure and the potential benefits of targeted therapeutic interventions.

A Western-type diet attenuates pulmonary hypertension with heart failure and cardiac cachexia in rats

Western-type diets (WD) constitute risk factors for disease but may have distinct effects in heart failure (HF) with cardiac cachexia (CC). We evaluated hemodynamic, metabolic, and inflammatory effects of short-term WD intake in pulmonary hypertension (PH) with CC. Male Wistar rats randomly received 60 mg · kg(-1) monocrotaline (M) or vehicle (C) and consumed either a 5.4-kcal · g(-1) WD (35% animal fat, 35% simple carbohydrate, 20% protein, 0.4% Na(+)) or a 2.9-kcal · g(-1) (3% vegetable fat, 60% complex carbohydrate, 16% protein, 0.25% Na(+)) normal diet (ND) for 5 wk. Mortality, energy intake, body weight (BW), metabolism, hemodynamics, histology, apoptosis, gene expression, transcription factors, and plasma cytokines were evaluated. Compared with the C-ND group, the M-ND group had PH, HF, and mortality that were significantly attenuated in M-WD. The extent of myocardial remodeling and apoptosis was higher in M-ND than in C-ND but lower in M-WD than in M-ND, while conversely, energy intake, BW, cholesterol, and TG plasma concentrations were lower in M-ND than in C-ND but higher in M-WD than in M-ND. M-ND had increased myocardial NF-κB transcription factor activity, endothelin-1, and cytokine overexpression and higher circulating cytokine concentrations than C-ND, which were lower in M-WD than in M-ND. PPARα activity, however, was lower in M-ND, but not in M-WD, compared with the respective C groups. WD attenuated PH and CC, ameliorating survival, myocardial function, metabolism, and inflammation, through transcription factor modulation, suggesting a beneficial role in CC.

Lipolytic effects of B-type natriuretic peptide 1-32 in adipose tissue of heart failure patients compared with healthy controls

OBJECTIVES

Our goal was to examine the role of B-type natriuretic peptide (BNP) in lipolysis regulation in heart failure (HF) patients.

BACKGROUND

Enhanced adipose tissue lipolysis can contribute to myocardial lipid overload, insulin resistance, and cachexia in advanced HF. Natriuretic peptides were recently recognized to stimulate lipolysis in healthy subjects.

METHODS

Ten nondiabetic HF patients (New York Heart Association functional class III, 50% nonischemic etiology) and 13 healthy subjects (control subjects) of similar age, sex, and body composition underwent a microdialysis study of subcutaneous abdominal adipose tissue. Four microdialysis probes were simultaneously perfused with 0.1 μM BNP(1-32,) 10 μM BNP(1-32), 10 μM norepinephrine (NE) or Ringer's solution. Outgoing dialysate glycerol concentration (DGC) was measured as an index of lipolysis.

RESULTS

Spontaneous lipolysis was higher in HF patients compared with control subjects (DGC: 189 ± 37 μmol/l vs. 152 ± 35 μmol/l, p < 0.01). Response to NE was similar (p = 0.35) in HF patients and control subjects (DGC increase of 1.7 ± 0.2-fold vs. 1.7 ± 0.4-fold). BNP(1-32) 10 μM markedly increased lipolysis in both HF patients and control subjects (DGC increase of 2.8 ± 0.5-fold vs. 3.2 ± 0.3-fold), whereas the response to 0.1 μM BNP(1-32) was more pronounced in HF patients (p = 0.02). In HF patients, spontaneous lipolysis positively correlated with insulin resistance and the response to BNP(1-32) negatively correlated with adiposity.

CONCLUSIONS

BNP(1-32) exerts strong lipolytic effects in humans. Despite marked elevation of plasma immunoreactive BNP, the responsiveness of adipose tissue to BNP(1-32) is not attenuated in HF, possibly reflecting a deficiency of endogenous bioactive BNP. Lipolytic effects of BNP can contribute to excessive fatty acid mobilization in advanced HF.

Resveratrol improves survival, hemodynamics and energetics in a rat model of hypertension leading to heart failure

Heart failure (HF) is characterized by contractile dysfunction associated with altered energy metabolism. This study was aimed at determining whether resveratrol, a polyphenol known to activate energy metabolism, could be beneficial as a metabolic therapy of HF. Survival, ventricular and vascular function as well as cardiac and skeletal muscle energy metabolism were assessed in a hypertensive model of HF, the Dahl salt-sensitive rat fed with a high-salt diet (HS-NT). Resveratrol (18 mg/kg/day; HS-RSV) was given for 8 weeks after hypertension and cardiac hypertrophy were established (which occurred 3 weeks after salt addition). Resveratrol treatment improved survival (64% in HS-RSV versus 15% in HS-NT, p<0.001), and prevented the 25% reduction in body weight in HS-NT (P<0.001). Moreover, RSV counteracted the development of cardiac dysfunction (fractional shortening −34% in HS-NT) as evaluated by echocardiography, which occurred without regression of hypertension or hypertrophy. Moreover, aortic endothelial dysfunction present in HS-NT was prevented in resveratrol-treated rats. Resveratrol treatment tended to preserve mitochondrial mass and biogenesis and completely protected mitochondrial fatty acid oxidation and PPARα (peroxisome proliferator-activated receptor α) expression. We conclude that resveratrol treatment exerts beneficial protective effects on survival, endothelium–dependent smooth muscle relaxation and cardiac contractile and mitochondrial function, suggesting that resveratrol or metabolic activators could be a relevant therapy in hypertension-induced HF.

The orally active melanocortin-4 receptor antagonist BL-6020/979: a promising candidate for the treatment of cancer cachexia

BACKGROUND: Under physiological conditions, the melanocortin system is a crucial part of the complex network regulating food intake and energy expenditure. In pathological states, like cachexia, these two parameters are deregulated, i.e., food intake is decreased and energy expenditure is increased-a vicious combination leading to catabolism. Agouti-related protein (AgRP), the endogenous antagonist at the melanocortin-4 receptor (MC-4R), was found to increase food intake and to reduce energy expenditure. This qualifies MC-4R blockade as an attractive mode of action for the treatment of cachexia. Based on this rationale, a novel series of small-molecule MC-4R antagonists was designed, from which the orally active compound BL-6020/979 (formerly known as SNT207979) emerged as the first promising development candidate showing encouraging pre-clinical efficacy and safety properties which are presented here. METHODS AND RESULTS: BL-6020/979 is an orally available, selective and potent MC-4R antagonist with a drug-like profile. It increased food intake and decreased energy expenditure in healthy wild-type but not in MC-4R deficient mice. More importantly, it ameliorated cachexia-like symptoms in the murine C26 adenocarcinoma model; with an effect on body mass and body composition and on the expression of catabolic genes. Moreover, BL-6020/979 showed antidepressant-like properties in the chronic mild stress model in rats and exhibits a favorable safety profile. CONCLUSION: The properties of BL-6020/979 demonstrated in animal models and presented here make it a promising candidate suitable for further development towards a first-in-class treatment option for cachexia that potentially opens up the opportunity to treat two hallmarks of the disease, i.e., decreased food intake and increased energy expenditure, with one drug.

Pathophysiology and treatment options for cardiac anorexia

The anorexia-cachexia syndrome (ACS) occurs in many chronic illnesses, such as cancer, AIDS, and chronic obstructive pulmonary disease in addition to chronic congestive heart failure (CHF). Comparable to other chronic states, the ACS complicates CHF and impacts its prognosis; however, the available treatment options for this syndrome remain unsatisfactory. This review article focuses on the complex pathophysiology of cardiac anorexia. We focus on the recent data demonstrating the relationships between central appetite-regulating structures, inflammatory processes, and neurohormonal activation, and their respective roles in the development of anorexia. We then describe the different treatment options and discuss some future prospects for the management for cardiac anorexia.

The role of myostatin in muscle wasting: an overview

Myostatin is an extracellular cytokine mostly expressed in skeletal muscles and known to play a crucial role in the negative regulation of muscle mass. Upon the binding to activin type IIB receptor, myostatin can initiate several different signalling cascades resulting in the upregulation of the atrogenes and downregulation of the important for myogenesis genes. Muscle size is regulated via a complex interplay of myostatin signalling with the insulin-like growth factor 1/phosphatidylinositol 3-kinase/Akt pathway responsible for increase in protein synthesis in muscle. Therefore, the regulation of muscle weight is a process in which myostatin plays a central role but the mechanism of its action and signalling cascades are not fully understood. Myostatin upregulation was observed in the pathogenesis of muscle wasting during cachexia associated with different diseases (i.e. cancer, heart failure, HIV). Characterisation of myostatin signalling is therefore a perspective direction in the treatment development for cachexia. The current review covers the present knowledge about myostatin signalling pathways leading to muscle wasting and the state of therapy approaches via the regulation of myostatin and/or its downstream targets in cachexia.

Breakthrough in cachexia treatment through a novel selective androgen receptor modulator?!

Cachexia, and particularly the loss of metabolically active lean tissue, leads to increased morbidity and mortality in affected patients. An impairment of strength and functional status is usually associated with cachexia. A variety of anabolic and appetite-stimulating agents have been studied in patients with cachexia caused by various underlying diseases. Overall, these studies have demonstrated that treatment can increase body weight and/or lean body mass. However, these therapies may have severe side effects, particularly when utilizing testosterone and related anabolic steroids targeting the androgen receptor. These side effects include cardiovascular problems, prostate hyperplasia and cancer in men, as well as virilization in women.

WSAVA nutritional assessment guidelines

OBJECTIVES

Careful assessment of the nutritional needs of cats and dogs must be taken into consideration in order to maintain optimum health, be part of a treatment regimen for a diseased state, or to maximize the quality of life in all animals. The goal of these World Small Animal Veterinary Association (WSAVA) Guidelines is that a nutritional assessment and specific nutritional recommendation is made for every patient on every visit. This will become known as the 5th Vital Assessment (5VA), following the four vital assessments of temperature, pulse, respiration and pain that are already addressed on each patient interaction.

EVALUATION OF NUTRITIONAL STATUS

A brief screening evaluation of nutritional status can be routinely and seamlessly performed during the history-taking and physical examination of every patient. Nutrition-related risk factors that can be easily identified from the history and physical examination include age (growing or old), suboptimal body condition score (overweight or thin), muscle loss, atypical or homemade diet, medical conditions or changes in appetite. An extended evaluation would follow if one or more risk factors is identified on screening. These guidelines provide criteria with which to evaluate the animal and the diet, as well as key feeding and environmental factors. In addition, recommendations for interpretation, analysis and action are included so that a plan for optimizing the animal's nutritional status can be instituted.

TEAM APPROACH

Client compliance with nutritional recommendations requires input from the veterinarian, veterinary technicians/nurses and hospital staff. A team approach to continuous nutritional education, implementation of appropriate protocols, and focused client communication, utilizing these WSAVA Nutritional Assessment Guidelines, is key to reaching this 5VA goal.

Ghrelin and cachexia: will treatment with GHSR-1a agonists make a difference for patients suffering from chronic wasting syndromes?

Cachexia is a syndrome of wasting and anorexia that worsens the prognosis of many chronic diseases including cancer, chronic kidney disease, chronic heart disease and chronic obstructive pulmonary disease. Properties of the orexigenic hormone ghrelin-including appetite-stimulation, weight-gain production and increased cardiac output make it a logical treatment for cachexia. While endogenous ghrelin levels are increased in the setting of cachexia, treatment with ghrelin and other GHSR-1a agonists in animal models of cachexia and in humans with cachexia has demonstrated consistent effects of increased appetite and improved weight gain. These positive effects occur in multiple underlying diseases associated with cachexia and appear to be sustained over treatment duration of up to 12 weeks. The mechanism of action in producing these effects is likely related to stimulation of central appetite centers such as the central melanocortin system and to increased growth hormone release, though ghrelin's effects may also relate to decreased systemic inflammation and other direct and indirect actions. Questions regarding the long-term safety of ghrelin treatment are still unanswered, as is the important question of whether successful treatment of cachexia will improve the prognosis of the underlying disease itself.

Treatment with iron of patients with heart failure with and without anemia

Iron deficiency is a common cause of anemia in otherwise healthy individuals and plays an important role in the development of anemia within the heart failure patient population. Iron-deficient heart failure patients experience worse symptoms and are less exercise tolerant than those without iron deficiency. These symptoms may occur even before clinical anemia is evident. This article reviews studies of the benefits of the use of intravenous iron to treat iron deficiency in anemic and nonanemic heart failure patients and an overview of the physiology and pathophysiology of iron metabolism in chronic heart failure.

Cachexia in heart disease: highlights from the ESC 2010

Cardiac cachexia is a co-morbidity that may develop in terminal stages of chronic heart failure (CHF). Up to 15% of ambulatory patients with heart failure are affected. Over the last decades, cardiac cachexia and alterations in muscle metabolism in heart disease have received increasing research interest. This article highlights some recent studies of cardiac cachexia that were presented at the annual meeting of the European Society of Cardiology in September 2010 in Stockholm, Sweden. Studies presented here were focused on effects of exercise training and protein degradation, particularly into the role of the ubiquitin-proteasome complex and its ubiquitin ligases MuRF-1 and MAFbx. Exercise training in patients with CHF was found to increase maximal oxygen consumption and to reduce MuRF-1 expression. Lysosomal muscle degradation does not seem to play a major role in patients with CHF, however, inflammatory cytokines such as tumor necrosis factor-a trigger muscle protein degradation. Other studies found that the serum levels of the adipokine adiponectin are elevated in patients with CHF and that these levels may be correlated with muscle mass, muscle strength in the arms, or with trunk fat mass. Another study showed that the expression of myostatin in skeletal muscle, a negative regulator of muscle growth that is essential for normal regulation of muscle mass, is decreased in spontaneously hypertensive rats with heart failure compared with control animals. This is also true for follistatin, a powerful antagonist, and its potential as a biomarker of muscle wasting. These findings may pave the way for effective treatment approaches to cardiac cachexia.

Nutritional assessment and support of the patient with acute heart failure

PURPOSE OF REVIEW

A significant number of patients hospitalized with heart failure are malnourished. Depletion of micronutrients, which is known to occur in heart failure for a variety of reasons, may contribute to myocardial abnormalities noted in heart failure. In this review, we focus on nutritional supplementation strategies that might improve myocardial performance and, as a consequence, decrease mortality and morbidity in these patients.

RECENT FINDINGS

The available data suggest that micronutrient and macronutrient supplementation may play a role in improving the myocardial metabolic abnormalities noted in heart failure. A recent trial of omega-3 fatty acid macronutrient supplementation showed a modest decrease in mortality and hospitalizations when used in patients with New York Heart Association class II-IV heart failure.

SUMMARY

Recommendations for nutritional support in patients with heart failure are difficult to make due to a lack of large randomized trials. Supplementation with omega-3 fatty acids, and micronutrients such as thiamine, coenzyme Q-10 and carnitine has shown promise in several studies. Since the data is not conclusive, large trials are needed to address whether these positive findings are reproducible in a wider subset of patients. In addition, these trials should study the combination of different micronutrients and macronutrients since heart failure patients are rarely deficient in just one micronutrient or macronutrient.

Anemia in heart failure: an overview of current concepts

Chronic heart failure is a substantial public health problem. Anemia is an important comorbidity frequently observed in patients with the disease and, in heart failure, anemia has only recently started to attract systematic epidemiological and therapeutical research endeavor. This article describes the many aspects of anemia in chronic heart failure, starting with the ongoing discussion of how to define anemia, which has important consequences for the estimation of its prevalence and incidence. Further, we discuss prognostic implications of anemia in patients with chronic or acute heart failure, the etiology of anemia in heart failure and treatment possibilities. Such therapeutic avenues embrace intravenous iron preparations and subcutaneous administration of erythropoietin and its derivatives, all of which have been extensively studied over the last several years. Finally, this article describes the potential costs incurred by treating anemic patients with heart failure.

Diabetes mellitus, cachexia and obesity in heart failure: rationale and design of the Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF)

BACKGROUND: Chronic heart failure (CHF) is increasing in prevalence. Patients with CHF usually have co-morbid conditions, but these have been subjected to little research and consequently there is a paucity of guidance on how to manage them. Obesity and diabetes mellitus are common antecedents of CHF and often complicate management and influence outcome. Cachexia is an ominous and often missed sign in patients with CHF. METHODS: This manuscript describes the rationale and the design of Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF), a prospective, multicentre, multinational, longitudinal, pathophysiological evaluation study, which is being conducted in 11 centres across six countries in the European Union and in Russia. We aim to recruit >1,600 patients with CHF due to various common aetiologies, irrespective of left ventricular ejection fraction, and with or without co-morbidities at study entry. In addition, >300 patients with type 2 diabetes mellitus without CHF and >150 healthy subjects will serve as control groups. Participants will be systematically investigated at annual intervals for up to 48 months. Additional investigations focusing on cellular and subcellular mechanisms, adipose and skeletal muscle tissue, and in endothelial progenitor cells will be performed in selected subgroups. CONCLUSIONS: SICA-HF will provide insights into common co-morbidities in CHF with a specific emphasis on diabetes mellitus and body mass. This will provide a more thorough pathophysiological understanding of the complexity of CHF that will help develop therapies tailored to manage specific co-morbidities.

Ghrelin and its potential in the treatment of eating/wasting disorders and cachexia

The gastrointestinal "hunger" hormone ghrelin is the only known circulating peripheral molecule with the ability to decrease body fat utilization and to increase body weight gain. Accordingly, due to ghrelin's effects to promote food intake while decreasing energy expenditure ghrelin may offer potential as a drug for treatment of eating/wasting disorders and cachexia. Therapeutic potential of ghrelin and ghrelin analogues to promote food intake and body weight gain was recently indicated in several clinical studies. The recent discovery of the ghrelin O-acyltransferase as the key enzyme responsible for ghrelin acylation has further deepened our understanding of ghrelin activation, thereby paving the way for more efficient targeting of the ghrelin pathway. Here, we summarize the current knowledge pertaining to the potential of the endogenous ghrelin system as a drug target for the treatment of eating/wasting disorders and cachexia.

Testosterone therapy: treatment of metabolic disturbances in heart failure

Heart failure (HF) is a complex progressive multisystem disease state with significant morbidity and mortality, which is not solely defined by pathology of the cardiovascular system but also is influenced by neurohormonal regulatory adjustments, peripheral cytokines, as well as hormonal and musculoskeletal dysfunction. Recent attention to the catabolic state found in patients with chronic heart failure has sparked interest in new potential targets for medical therapy. In particular, as many as 26% to 37% of men affected with HF have been found to be testosterone deficient. The severity of androgen deficiency has been shown to correlate with symptoms, functional class, and prognosis in patients with heart failure. Testosterone supplementation has been an accepted therapy in hypogonadal men with fatigue, muscle wasting, and sexual dysfunction for some time. Patients with severe HF show a similar constellation of symptoms and hypothetically would benefit from androgen replacement. Recent clinical studies have confirmed that functional, biochemical, and cardiopulmonary status in patients with HF have significant improvements when treated with testosterone supplementation. Symptomatic improvements may be obtainable in hypogonadal patients with HF who receive supplemental testosterone. This review seeks to outline the cardiovascular and peripheral effects of testosterone supplementation in patients with chronic HF.

Novel treatment approaches to cachexia and sarcopenia: highlights from the 5th Cachexia Conference

Cachexia is an illness that may occur in terminal stages of many chronic illnesses including cancer, chronic heart failure, chronic renal failure or chronic obstructive pulmonary disease. Effective treatments are urgently needed in order to improve the patients' quality of life and their survival. We report highlights from the 5th Cachexia Conference held in December 2009 in Barcelona, Spain. Novel therapeutic approaches shown here include melanocortin-4 receptor antagonists, myostatin inhibition, beta-blockers, IL-6 antagonism synthetic ghrelin and vitamin D.

Growth hormone and testosterone in heart failure therapy

IMPORTANCE OF THE FIELD

Heart failure is a progressive disease affecting millions of people worldwide. The disease carries a significantly high morbidity and mortality risk. There are multiple pharmaceutical options to decrease this risk and prolong survival; however, despite optimization of medical management, several patients still await heart transplant, the only definitive cure for heart failure. To slow the progression of disease preventing need for transplantation, improve clinical symptoms, and improve heart failure outcomes, there is a persistent need to discover new therapeutic strategies. Of interest, low growth hormone and testosterone levels have been associated with a worsening degree of heart failure. Many studies have begun to show a clinical improvement in heart failure symptoms when these levels are corrected with hormonal therapy. These findings, although mixed, are promising and indicate that both testosterone and growth hormone therapy should be considered as adjunctive therapy in advanced heart failure patients.

AREAS COVERED IN THIS REVIEW

This review discusses the physiology of both of these natural hormones, their therapeutic effects in heart failure and data from the published literature on studies using growth hormone or testosterone in patients with chronic heart failure. An extensive search of PubMed was conducted for topics on heart failure, growth hormone, insulin-like growth factor, testosterone, their physiology and pathophysiology, and trials in which they have been used as therapeutic interventions between 1989 and 2009.

WHAT THE READER WILL GAIN

The reader will gain an understanding of the intricate balance of both of these hormones in the disease state of heart failure. In addition, the trials conducted using these hormones in pharmacotherapy for heart failure are discussed along with proposed theories for interstudy variability.

TAKE HOME MESSAGE

Testosterone deficiency and growth hormone resistance are positively associated with a poor state of heart failure. Treatment of deficiency improves outcomes in heart failure; however, there is a significant paucity of data with regard to testosterone and heart failure as well as a significant amount of study variability with growth hormone and heart failure.

Systemic zinc redistribution and dyshomeostasis in cancer cachexia

Cachexia affects up to two thirds of all cancer patients and is a significant cause of morbidity and mortality. It is a complex metabolic syndrome associated with the underlying illness and characterized by loss of skeletal muscle tissue with or without loss of fat mass. Cachexia's other prominent clinical symptoms include anorexia, systemic inflammation, pediatric growth failure, and hypogonadism. The relationship between the symptoms of cancer cachexia and the underlying illness is unclear, and there is an urgent need for a better understanding of the pathophysiology of this syndrome. Normal Zn metabolism is often disrupted in cancer patients, but the possible effects of systemic Zn dyshomeostasis in cachexia have not been investigated. We propose that the acute phase response can mediate Zn redistribution and accumulation in skeletal muscle tissue and contribute to the activation of the ubiquitin-proteasome pathway that regulates protein catabolism. This chronic redistribution deprives Zn from other tissues and organs and compromises critical physiological functions in the body. The cardinal symptoms of Zn deficiency are anorexia, systemic inflammation, growth failure in children, and hypogonadism. These symptoms also prominently characterize cancer cachexia suggesting that the role of systemic Zn dyshomeostasis in cachexia should be investigated.

The effects of a high-caloric protein-rich oral nutritional supplement in patients with chronic heart failure and cachexia on quality of life, body composition, and inflammation markers: a randomized, double-blind pilot study

The prevalence of cardiac cachexia in chronic heart failure is approximately 5% to 15% and 18-month mortality rates can reach 50%. Treatment with angiotensin-converting enzyme inhibitors and beta-blockers may confer some benefit but no proven therapy exists. We tested the effects of an oral nutritional supplement in cachectic patients with heart failure. This was a prospective, randomized, double-blind, placebo-controlled pilot study which randomized 29 patients to a high-caloric (600 kcal) high-protein (20 g) oral nutritional supplement or placebo for a duration of 6 weeks in addition to the patients' usual food intake. At baseline, 6 weeks, and 18 weeks, we measured body weight, quality of life, body composition, heart function, laboratory parameters, and exercise performance. Edema-free body weight increased in 19 of 20 patients receiving intervention at 6 weeks and in 17 of 19 patients at 18 weeks with an average weight gain of 2.0 ± 1.7 kg (3.1 ± 2.4%, p = 0.0001) and 2.3 ± 3.1 kg (3.6 ± 4.7%, p = 0.007) at 6 and 18 weeks, respectively. Most of the weight gain was fat tissue with an absolute gain of 1.5 ± 1.7 kg (p = 0.003) and 1.6 ± 2.7 kg (p = 0.008). A significant improvement in quality of life and decrease in serum levels of tumor necrosis factor-α were observed (p < 0.05 for both). We demonstrated the feasibility of oral nutritional supplement in cachectic patients with heart failure and significant clinical benefit in terms of body size and body composition, laboratory parameters, and quality of life (www.clinicaltrials.gov identifier NCT00654719).

Cachexia as a major underestimated and unmet medical need: facts and numbers

Cachexia is a serious, however underestimated and underrecognised medical consequence of malignant cancer, chronic heart failure (CHF), chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), cystic fibrosis, rheumatoid arthritis, Alzheimer's disease, infectious diseases, and many other chronic illnesses. The prevalence of cachexia is high, ranging from 5% to 15% in CHF or COPD to 60% to 80% in advanced cancer. By population prevalence, the most frequent cachexia subtypes are in order: COPD cachexia, cardiac cachexia (in CHF), cancer cachexia, and CKD cachexia. In industrialized countries (North America, Europe, Japan), the overall prevalence of cachexia (due to any disease) is growing and currently about 1%, i.e., about nine million patients. The relative prevalence of cachexia is somewhat less in Asia, but is a growing problem there as well. In absolute terms, cachexia is, in Asia (due to the larger population), as least as big a problem as in the Western world. Cachexia is also a big medical problem in South America and Africa, but data are scarce. A consensus statement recently proposed to diagnose cachexia in chronic diseases when there is weight loss exceeding 5% within the previous 3-12 months combined with symptoms characteristic for cachexia (e.g., fatigue), loss of skeletal muscle and biochemical abnormalities (e.g., anemia or inflammation). Treatment approaches using anabolics, anti-catabolic therapies, appetite stimulants, and nutritional interventions are under development. A more thorough understanding of the pathophysiology of cachexia development and progression is needed that likely will lead to combination therapies being developed. These efforts are greatly needed as presence of cachexia is always associated with high-mortality and poor-symptom status and dismal quality of life. It is thought that in cancer, more than 30% of patients die due to cachexia and more than 50% of patients with cancer die with cachexia being present. In other chronic illnesses, one can estimate that up to 30% of patients die with some degree of cachexia being present. Mortality rates of patients with cachexia range from 10% to 15% per year (COPD), to 20% to 30% per year (CHF, CKD) to 80% in cancer.

Comparison of direct body composition assessment methods in patients with chronic heart failure

BACKGROUND

We examined the validity of leg-to-leg bioelectrical impedance analysis (BIA) and near-infrared interactance (NIR) to assess body composition in chronic heart failure (CHF) patients.

METHODS AND RESULTS

A total of 140 patients with CHF were enrolled in this cross-sectional study between June 2008 and July 2009. Dual energy x-ray absorptiometry (DEXA) served as the reference standard. A priori, desired precision levels were set at ± 3.5% body fat and ± 3.5 kg lean body mass. Mean age was 63, 74% were male, and 90% were Caucasian. BIA- and NIR-ascertained percent body fat and lean body mass were highly correlated to DEXA. Mean differences and limits of agreement for NIR were -0.3% ± 5.1% for percent body fat and 2.9 kg ± 4.3 kg for lean body mass. Mean difference and limits of agreement for BIA percent body fat was 0.8% ± 5.8%. BIA lean body mass showed poor agreement with DEXA because of variable limits of agreement across the range of measurement (Pitman's test P < .0001).

CONCLUSIONS

In patients with CHF, both NIR and BIA accurately measure body fat. However, both methods were imprecise. NIR overestimated lean body mass and BIA was not useful to assess this parameter. Further study is required, including examination of the utility of these field methods in serially assessing body composition.

Update on clinical trials of growth factors and anabolic steroids in cachexia and wasting

This article and others that focused on the clinical features, mechanisms, and epidemiology of skeletal muscle loss and wasting in chronic diseases, which include chronic kidney disease, cancer, and AIDS, were presented at a symposium entitled "Cachexia and Wasting: Recent Breakthroughs in Understanding and Opportunities for Intervention," held at Experimental Biology 2009. The clinical and anabolic efficacy of specific growth factors and anabolic steroids (eg, growth hormone, testosterone, megestrol acetate) in malnutrition and other catabolic states has been the subject of considerable research during the past several decades. Research on the effects of these agents in cachexia or wasting conditions, characterized by progressive loss of skeletal muscle and adipose tissue, focused on patients with AIDS in the early 1990s, when the devastating effects of the loss of body weight, lean body mass, and adipose tissue were recognized as contributors to these patients' mortality. These same agents have also been studied as methods to attenuate the catabolic responses observed in cancer-induced cachexia and in wasting induced by chronic obstructive pulmonary disease, congestive heart failure, renal failure, and other conditions. This article provides an updated review of recent clinical trials that specifically examined the potential therapeutic roles of growth hormone, testosterone, oxandrolone, and megestrol acetate and emerging data on the orexigenic peptide ghrelin, in human cachexia and wasting.

Biomarkers for chronic heart failure : diagnostic, prognostic, and therapeutic challenges

Cardiac biomarkers are very important in diagnosis, risk stratification, and management of patients with heart failure. Although not meeting all criteria for an ideal biomarker, natriuretic peptides primarily have a diagnostic and prognostic role. Other routinely available and newly emerging biomarkers have a complementary role in patient management; thus multimarker strategy might be warranted in future. The quest for a single marker or a combination is ongoing and several established, widely available biomarkers might have been overlooked in the field of heart failure. The authors review some of those biomarkers and speculate on the possible roles of combining two or more of them.

The pathophysiology of cardiac cachexia

PURPOSE OF REVIEW

Cardiac cachexia, the loss of lean body mass that affects a large proportion of patients with chronic heart failure, is associated with increased morbidity and mortality. The pathophysiology of cardiac cachexia is complex and multifactorial, but recent studies are providing new information that is helping to clarify the pathophysiology and new targets for treatment.

RECENT FINDINGS

New attention is being paid to developing a definition as well as a clinically relevant way to diagnose this syndrome. The adverse clinical effects of cachexia are being emphasized by new research on the obesity paradox, suggesting that cardiac cachexia is such a detrimental process that obesity actually confers a survival benefit. This information is useful in developing practical approaches to managing body weight and lean tissue in chronic heart failure patients and may provide therapeutic targets. New mechanisms and pathways that mediate cardiac cachexia are being identified and appear to act by increasing energy requirements, reducing energy intake, impairing nutrient absorption, and causing metabolic alterations.

SUMMARY

Recent studies have helped to better delineate multifactorial mechanisms in the pathophysiology of cardiac cachexia that may lead to more effective treatments to address this common and important syndrome in patients with chronic heart failure.

Update on melanocortin interventions for cachexia: progress toward clinical application

Cachexia is a devastating syndrome of body wasting that is associated with multiple common chronic diseases including cancer, chronic kidney disease, and chronic heart failure. These underlying diseases are associated with increased levels of inflammatory cytokines and result in anorexia, increased resting energy expenditure, and loss of fat and lean body mass. Prior experiments have implicated the central melanocortin system in the hypothalamus with the propagation of these symptoms of cachexia. Pharmacologic blockade of this system using melanocortin antagonists causes attenuation of the signs of cachexia in laboratory models. Recent advances in our knowledge of this disease process have involved further elucidation of the pathophysiology of melanocortin activation and demonstration of the efficacy of melanocortin antagonists in new models of cachexia, including cardiac cachexia. In addition, small molecule antagonists of the melanocortin-4 receptor continue to be introduced, including ones with oral bioavailability. These developments generate optimism that melanocortin antagonism will be used to treat humans with disease-associated cachexia. However, to date, human application has remained elusive and it is unclear when we will know whether humans with cachexia would benefit from treatment with these compounds.

Calories and cachexia

PURPOSE OF REVIEW

Anorexia and weight loss are associated with increased mortality in cachectic patients. The role of caloric supplementation is controversial. The purpose of this review is to examine the role of calorie supplementation in cachexia.

RECENT FINDINGS

Caloric supplementation improves outcomes in malnourished hospital patients and malnourished older persons. It may improve the quality of life in cancer patients and for those persons receiving palliative care. Caloric supplementation should include a balanced essential amino acid supplement given at least twice a day. The role of eicosapentanoic acid as a supplement is controversial. All caloric supplements should be given between and not with meals.

SUMMARY

Caloric supplementation rich in protein and with adequate vitamin D should be given between meals to all patients with cachexia.

Animal models of anorexia and cachexia

BACKGROUND: Cachexia is a devastating syndrome of body wasting that worsens quality of life and survival for patients suffering from diseases such as cancer, chronic kidney disease and chronic heart failure. Successful treatments have been elusive in humans, leaving a clear need for the development of new treatment compounds. Animal models of cachexia are able to recapitulate the clinical findings from human disease and have provided a much-needed means of testing the efficacy of prospective therapies. OBJECTIVE: This review focuses on animal models of cachexia caused by cancer, chronic heart failure and chronic kidney disease, including the features of these models, their implementation, and commonly-followed outcome measures. CONCLUSION: Given a dire clinical need for effective treatments of cachexia, animal models will continue a vital role in assessing the efficacy and safety of potential treatments prior to testing in humans. Also important in the future will be the use of animal models to assess the durability of effect from anti-cachexia treatments and their effect on prognosis of the underlying disease states.