Prevention of liver cancer cachexia-induced cardiac wasting and heart failure.

AIMS: Symptoms of cancer cachexia (CC) include fatigue, shortness of breath, and impaired exercise capacity, which are also hallmark symptoms of heart failure (HF). Herein, we evaluate the effects of drugs commonly used to treat HF (bisoprolol, imidapril, spironolactone) on development of cardiac wasting, HF, and death in the rat hepatoma CC model (AH-130). METHODS AND RESULTS: Tumour-bearing rats showed a progressive loss of body weight and left-ventricular (LV) mass that was associated with a progressive deterioration in cardiac function. Strikingly, bisoprolol and spironolactone significantly reduced wasting of LV mass, attenuated cardiac dysfunction, and improved survival. In contrast, imidapril had no beneficial effect. Several key anabolic and catabolic pathways were dysregulated in the cachectic hearts and, in addition, we found enhanced fibrosis that was corrected by treatment with spironolactone. Finally, we found cardiac wasting and fibrotic remodelling in patients who died as a result of CC. In living cancer patients, with and without cachexia, serum levels of brain natriuretic peptide and aldosterone were elevated. CONCLUSION: Systemic effects of tumours lead not only to CC but also to cardiac wasting, associated with LV-dysfunction, fibrotic remodelling, and increased mortality. These adverse effects of the tumour on the heart and on survival can be mitigated by treatment with either the ß-blocker bisoprolol or the aldosterone antagonist spironolactone. We suggest that clinical trials employing these agents be considered to attempt to limit this devastating complication of cancer.

The small molecule ACM-001 improves cardiac function in a rat model of severe cancer cachexia.

AIMS: Cachexia, a common manifestation of malignant cancer, is not only associated with weight loss, but also with severe cardiac atrophy and impaired cardiac function. Here, we investigated the effects of ACM-001 (0.3 or 3 mg/kg/day) in comparison to carvedilol (3 or 30 mg/kg/day), metropolol (50 or 100 mg/kg/day), nebivolol (1 or 10 mg/kg/day) and tertatolol (0.5 or 5 mg/kg/day) on cardiac mass and function in a rat cancer cachexia model. METHODS AND RESULTS: Young male Wistar Han rats were inoculated i.p. with 108 Yoshida hepatoma AH-130 cells and treated once daily with verum or placebo by gavage. Cardiac function (echocardiography), body weight and body composition (nuclear magnetic resonance scans) were assessed. The hearts of animals were euthanized on day 11 (placebo and 3 mg/kg/day ACM-001) were used for signalling studies. Beta-blockers had no effect on tumour burden. ACM-001 reduced body weight loss (placebo: -34 ± 2.4 g vs. 3 mg/kg/day ACM-001: -14.8 ± 8.4 g, p = 0.033). Lean mass wasting was attenuated (placebo: -16.5 ± 2.34 g vs. 3 mg/kg/day ACM-001: -2.4 ± 6.7 g, p = 0.037), while fat loss was similar (p = 0.4) on day 11. Placebo animals lost left ventricular mass (-101 ± 14 mg), which was prevented only by 3 mg/kg/day ACM-001 (7 ± 25 mg, p < 0.01 vs. placebo). ACM-001 improved the ejection fraction (EF) (ΔEF: placebo: -24.3 ± 2.6 vs. 3 mg/kg/day ACM-001: 0.1 ± 2.9, p < 0.001). Cardiac output was 50% lower in the placebo group (-41 ± 4 ml/min) compared to baseline, while 3 mg/kg/day ACM-001 preserved cardiac output (-5 ± 8 ml/min, p < 0.01). The molecular mechanisms involved inhibition of protein degradation and activation of protein synthesis pathways. CONCLUSION: This study shows that 3 mg/kg/day ACM-001 restores the anabolic/catabolic balance in cardiac muscle leading to improved function. Moreover, not all beta-blockers have similar effects.

The atypical ß-blocker S-oxprenolol reduces cachexia and improves survival in a rat cancer cachexia model.

BACKGROUND: Beta-blockers and selected stereoisomers of beta-blockers, like bisoprolol and S-pindolol (ACM-001), have been shown to be effective in preclinical cancer cachexia models. Here, we tested the efficacy of stereoisomers of oxprenolol in two preclinical models of cancer cachexia-the Yoshida AH-130 rat model and the Lewis lung carcinoma (LLC) mouse model. METHODS AND RESULTS: In the Yoshida AH130 hepatoma rat cancer cachexia model and compared with placebo, 50 mg/kg/d S-oxprenolol (HR: 0.49, 95% CI: 0.28-0.85, P = 0.012) was superior to 50 mg/kg/d R-oxprenolol (HR: 0.83, 95% CI 0.38-1.45, P = 0.51) in reducing mortality (= reaching ethical endpoints). Combination of the three doses (12.5, 25 and 50 mg/kg/d) that had a significant effect on body weight loss in the S-oxprenolol groups vs the same combination of the R-oxprenolol groups lead to a significantly improved survival of S-oxprenolol vs R-oxprenolol (HR: 1.61, 95% CI: 1.08-2.39, P = 0.0185). Interestingly, there is a clear dose dependency in S-oxprenolol-treated (5, 12.5, 25 and 50 mg/kg/d) groups, which was not observed in groups treated with R-oxprenolol. A dose-dependent attenuation of weight and lean mass loss by S-oxprenolol was seen in the Yoshida rat model, whereas R-oxprenolol had only had a significant effect on fat mass. S-oxprenolol also non-significantly reduced weight loss in the LLC model and also improved muscle function (grip strength 428 ± 25 and 539 ± 37 g/100 g body weight for placebo and S-oxprenolol, respectively). However, there was only a minor effect on quality of life indicators food intake and spontaneous activity in the Yoshida model (25 mg/kg/S-oxprenolol: 11.9 ± 2.5 g vs placebo: 4.9 ± 0.8 g, P = 0.013 and also vs 25 mg/kg/d R-oxprenolol: 7.5 ± 2.6 g, P = 0.025). Both enantiomers had no effects on cardiac dimensions and function at the doses used in this study. Western blotting of proteins involved in the anabolic/catabolic homoeostasis suggest that anabolic signalling is persevered (IGF-1 receptor, Akt) and catabolic signalling is inhibited (FXBO-10, TRAF-6) by S-pindolol, but not he R-enantiomer. Expression of glucose transporters Glut1 and Glut 4 was similar in all groups, as was AMPK. CONCLUSIONS: S-oxprenolol is superior to R-oxprenolol in cancer cachexia animal models and shows promise for a human application in cancer cachexia.

Inhibition of xanthine oxidase reduces wasting and improves outcome in a rat model of cancer cachexia.

Cachexia is a common co-morbidity in cancer occurring in up to 80% of patients depending on the type of cancer. Uric acid (UA), the end-product of the purine metabolism, is elevated in cachexia due to tissue wasting and upregulated xanthine oxidase (XO) activity. High serum UA levels indicate increased XO-dependent production of oxygen free radicals (reactive oxygen species; ROS) and correlate with metabolic illness and poor survival. We hypothesized that XO-inhibition might reduce inflammatory signals accounting for tissue wasting and improve survival in experimental cancer cachexia. Animals were inoculated intraperitoneally with AH-130 hepatoma cells and treated with two XO-inhibitors: allopurinol [Allo, low (LD) and high dose (HD) 4 and 40 mg/kg/d] and its more effective active metabolite oxypurinol (Oxy, 4 and 40 mg/kg/d) or placebo for 15 days. Weight loss and tissue wasting of both fat and lean tissue (assessed by NMR-scanning) was reduced by both LD and HD Allo and LD-Oxy, but not by HD-Oxy. A robust induction of XO-activity for generation of reactive oxygen species was seen in the placebo group (assessed by electron paramagnetic spectroscopy), which was reduced by XO-inhibition. Increased ROS induced cytokine signaling, proteolytic activity and tissue degradation were all attenuated by XO inhibition. Survival was significantly and dose dependently improved. Food intake and spontaneous locomotor activity were higher, indicating a higher quality of life. Inhibition of XO can reduce tissue wasting and improve survival in cancer cachexia and clearly clinical studies are needed.

The erythropoietin-derived peptide ARA 284 reduces tissue wasting and improves survival in a rat model of cancer cachexia.

BACKGROUND: Cancer cachexia (CC) is a severe complication during the last stages of the disease, which is characterized by the substantial loss of muscle and fat mass. Currently, there is no effective treatment of CC. Erythropoietin plays tissue-protective role in different tissues. Based on the structure of erythropoietin, small non-erythropoietic peptides were synthesized, which activate tissue-protective signalling pathways. METHODS: Here, we investigated the influence of the tissue-protective peptide ARA 284 on CC in rats using the Yoshida hepatoma model. RESULTS: Treatment with ARA 284 (1.7 µg/kg/day) counteracted the loss of body weight (12.46 ± 4.82% ARA 284 vs. 26.85 ± 0.88% placebo, P < 0.01), fat mass (P < 0.01), and lean mass (P < 0.01). It improved spontaneous activity of ARA 284-treated animals. Further, gastrocnemius mass was increased (13.2% ARA 284 vs. placebo, P < 0.01) in association with induced p-Akt (P < 0.01) and decreased in p-p38 MAPK, GSK-3ß, and myostatin (all P < 0.01), suggesting an induction of anabolic pathways. At the same time, we observed the significant increase in the survival of animals by high-dose ARA 284 treatment (hazard ratio: 0.46, 95% confidence interval: 0.23-0.94, P = 0.0325). CONCLUSIONS: Taken together these results suggest that ARA 284 can be considered beneficial in experimental CC and it remains to be seen, if it can have similar beneficial effects in CC patient.

MT-102 prevents tissue wasting and improves survival in a rat model of severe cancer cachexia.

BACKGROUND: Cachexia, a common manifestation of malignant cancer, is associated with wasting of skeletal muscle and fat tissue. In this study, we investigated the effects of a new first in class anabolic catabolic transforming agent on skeletal muscle in a rat model of cancer cachexia. METHODS: Young male Wistar Han rats were intraperitoneally inoculated with 108 Yoshida hepatoma AH-130 cells and once daily treated with 0.3 mg kg-1 , 3 mg kg-1 MT-102, or placebo by gavage. RESULTS: Three mg kg-1 d-1 MT-102 not only prevented progressive loss of fat mass (-6 ± 2 g vs -12 ± 1 g; P < 0.001); lean mass (+1 ± 10 g vs. -37 ± 2 g; P < 0.001) and body weight (+1 ± 13 g vs. -60 ± 2 g; P < 0.001) were remained. Quality of life was also improved as indicated by a higher food intake 12.9 ± 3.1 g and 4.3 ± 0.5 g, 3 mg kg-1 d-1 MT-102 vs. placebo, respectively, P < 0.001) and a higher spontaneous activity (52 369 ± 6521 counts/24 h and 29 509 ± 1775 counts/24 h, 3 mg·kg-1 d-1 MT-102 vs. placebo, respectively, P < 0.01) on Day 11. Most importantly, survival was improved (HR = 0.29; 95% CI: 0.16-0.51, P < 0.001). The molecular mechanisms behind these effects involve reduction of overall protein degradation and activation of protein synthesis, assessed by measurement of proteasome and caspase-6 activity or Western blot analysis, respectively. CONCLUSIONS: The present study shows that 3 mg kg-1 MT-102 reduces catabolism, while inducing anabolism in skeletal muscle leading to an improved survival.

Cardiac expression of neutrophil gelatinase-associated lipocalin in a model of cancer cachexia-induced cardiomyopathy.

AIMS: Cachexia is a severe consequence of cancer. Although cancer-induced heart atrophy leads to cardiac dysfunction and heart failure (HF), biomarkers for their diagnosis have not been identified. Neutrophil gelatinase-associated lipocalin (NGAL) is an aldosterone-responsive gene increased in HF. We studied NGAL and its association with aldosterone levels in a model of cancer cachexia-induced cardiomyopathy. METHODS AND RESULTS: Rats were injected with Yoshida 108 AH-130 hepatoma cells to induce tumour. Cachectic rats were treated daily, for 16 days, with placebo or with 5 or 50 mg/kg/day of spironolactone. Cardiac function was analysed by echocardiography at baseline and at Day 11. Weight loss and atrophy of lean body and fat mass of cachectic rats were significantly attenuated by spironolactone. Cardiac dysfunction of tumour-bearing rats was improved by spironolactone. Plasma aldosterone was up-regulated from 337 ± 7 pg/mL in sham animals to 591 ± 31 pg/mL in the cachectic rats (P < 0.001 vs. sham). Treatment with 50 or 5 mg/kg/day of spironolactone reduced plasma aldosterone to 396 ± 22 and 391 ± 25 pg/mL (P < 0.01 vs. placebo). Plasma levels of NGAL were also increased in cachectic rats (1.462 ± 0.3603 µg/mL) than in controls (0.0936 ± 6 µg/mL, P < 0.001). Spironolactone treatment (50 mg/kg/day) significantly reduced cardiac mRNA and protein NGAL levels (P < 0.05 and P < 0.001 vs. placebo, respectively). NGAL mRNA and protein levels were overexpressed in cachectic animal hearts treated with placebo, compared with control (P < 0.05 and P < 0.01 vs. sham). Spironolactone treatment at 50 mg/kg/day reduced significantly cardiac NGAL (P < 0.05 and P < 0.001 vs. placebo). CONCLUSIONS: Cancer cachexia induced increased levels of aldosterone and NGAL, contributing to worsening cardiac damage in cancer cachexia-induced cardiomyopathy. Spironolactone treatment may greatly attenuate cardiac dysfunction and lean mass atrophy associated with cancer cachexia.

Skeletal muscle wasting in chronic heart failure.

Patients suffering from chronic heart failure (CHF) show an increased prevalence (~20% in elderly CHF patients) of loss of muscle mass and muscle function (i.e. sarcopenia) compared with healthy elderly people. Sarcopenia, which can also occur in obese patients, is considered a strong predictor of frailty, disability, and mortality in older persons and is present in 5-13% of elderly persons aged 60-70 years and up to 50% of all octogenarians. In a CHF study, sarcopenia was associated with lower strength, reduced peak oxygen consumption (peak VO2 , 1173 ± 433 vs. 1622 ± 456 mL/min), and lower exercise time (7.7 ± 3.8 vs. 10.22 ± 3.0 min, both P < 0.001). Unfortunately, there are only very limited therapy options. Currently, the main intervention remains resistance exercise. Specialized nutritional support may aid the effects of resistance training. Testosterone has significant positive effects on muscle mass and function, and low endogenous testosterone has been described as an independent risk factor in CHF in a study with 618 men (hazard ratio 0.929, P = 0.042). However, the use of testosterone is controversial because of possible side effects. Selective androgen receptor modulators have been developed to overcome these side effects but are not yet available on the market. Further investigational drugs include growth hormone, insulin-like growth factor 1, and several compounds that target the myostatin pathway. The continuing development of new treatment strategies and compounds for sarcopenia, muscle wasting regardless of CHF, and cardiac cachexia makes this a stimulating research area.

Acylated ghrelin treatment normalizes skeletal muscle mitochondrial oxidative capacity and AKT phosphorylation in rat chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) is associated with skeletal muscle abnormalities contributing to exercise intolerance, muscle loss, and negative impact on patient prognosis. A primary role has been proposed for mitochondrial dysfunction, which may be induced by systemic and tissue inflammation and further contribute to low insulin signalling. The acylated form of the gastric hormone ghrelin (AG) may improve mitochondrial oxidative capacity and insulin signalling in both healthy and diseased rodent models. METHODS: We investigated the impact of AG continuous subcutaneous administration (AG) by osmotic minipump (50 nmol/kg/day for 28 days) compared with placebo (P) on skeletal muscle mitochondrial enzyme activities, mitochondrial biogenesis regulators transcriptional expression and insulin signalling in a rodent post-myocardial infarction CHF model. RESULTS: No statistically significant differences (NS) were observed among the three group in cumulative food intake. Compared with sham-operated, P had low mitochondrial enzyme activities, mitochondrial biogenesis regulators transcripts, and insulin signalling activation at AKT level (P < 0.05), associated with activating nuclear translocation of pro-inflammatory transcription factor nuclear factor-κB. AG completely normalized all alterations (P < 0.05 vs P, P = NS vs sham-operated). Direct AG activities were strongly supported by in vitro C2C12 myotubes experiments showing AG-dependent stimulation of mitochondrial enzyme activities. No changes in mitochondrial parameters and insulin signalling were observed in the liver in any group. CONCLUSIONS: Sustained peripheral AG treatment with preserved food intake normalizes a CHF-induced tissue-specific cluster of skeletal muscle mitochondrial dysfunction, pro-inflammatory changes, and reduced insulin signalling. AG is therefore a potential treatment for CHF-associated muscle catabolic alterations, with potential positive impact on patient outcome.

Erythropoietin improves cardiac wasting and outcomes in a rat model of liver cancer cachexia.

BACKGROUND: Erythropoietin administration, which is clinically used in cancer patients with cancer-induced anemia, has also potentially beneficial effects on nonhematopoietic organs. We assessed the effects of erythropoietin on cancer cachexia progression and cardiac wasting compared with placebo using the Yoshida hepatoma model. METHODS: Wistar rats were divided in a sham group (n=10) and a tumor-bearing group (n=60). The tumor-bearing group was further randomized to placebo (n=28), 500Unit/kg/day (n=16) or 5000Unit/kg/day of erythropoietin (n=16). Body composition was measured using nuclear magnetic resonance spectroscopy, cardiac function using echocardiography, physical activity using infrared monitoring system. RESULTS: Tumor-bearing rats with high dose erythropoietin led to a significant improvement on survival compared with placebo (hazard ratio: 0.43, 95%CI: 0.20-0.92, p=0.030), though low dose erythropoietin did not reach significance (hazard ratio: 0.46, 95%CI: 0.22-1.02, p=0.056). Loss of body weight, wasting of lean mass, fat mass, and reduced physical activity were ameliorated in rats treated with both low and high doses of erythropoietin (p<0.05, all). Moreover, reduced left ventricular mass and left ventricular systolic function were also ameliorated in rats treated with low and high doses of erythropoietin (p<0.05, respectively). CONCLUSIONS: Overall, the present data support that cardiac wasting induced by cancer cachexia plays an important role which leads to impaired survival, provided that the erythropoietin could be an effective therapeutic approach for cancer cachexia progression and cardiac wasting.

Megestrol acetate improves cardiac function in a model of cancer cachexia-induced cardiomyopathy by autophagic modulation.

BACKGROUND: Cachexia is a complex metabolic syndrome associated with cancer. One of the features of cachexia is the loss of muscle mass, characterized by an imbalance between protein synthesis and protein degradation. Muscle atrophy is caused by the hyperactivation of some of the main cellular catabolic pathways, including autophagy. Cachexia also affects the cardiac muscle. As a consequence of the atrophy of the heart, cardiac function is impaired and mortality is increased. Anti-cachectic therapy in patients with cancer cachexia is so far limited to nutritional support and anabolic steroids. The use of the appetite stimulant megestrol acetate (MA) has been discussed as a treatment for cachexia. METHODS: In this study the effects of MA were tested in cachectic tumour-bearing rats (Yoshida AH-130 ascites hepatoma). Rats were treated daily with 100 mg/kg of MA or placebo starting one day after tumour inoculation, and for a period of 16 days. Body weight and body composition were assessed at baseline and at the end of the study. Cardiac function was analysed by echocardiography at baseline and at day 11. Locomotor activity and food intake were assessed before tumour inoculation and at day 11. Autophagic markers were assessed in gastrocnemius muscle and heart by western blot analysis. RESULTS: Treatment with 100 mg/kg/day MA significantly attenuated the loss of body weight (-9 ± 12%, P < 0.05) and the wasting of lean and fat mass (-7.0 ± 6% and -22.4 ± 3 %, P < 0.001 and P < 0.05, respectively). Administration of 100 mg/kg/day MA significantly protected the heart from general atrophy (633.8 ± 30 mg vs. placebo 474 ± 13 mg, P < 0.001). Tumour-bearing rats displayed cardiac dysfunction, as indicated by the significant impairment of the left ventricular ejection fraction, the left ventricular fractional shortening, the stroke volume, the end dyastolic volume, and the end systolic volume. In contrast, MA significantly improved left ventricular ejection fraction, left ventricular fractional shortening, and left ventricular end systolic volume. Western blotting analysis showed an upregulation of the autophagic pathway in the gastrocnemius and hearts of the placebo-treated tumour-bearing rats. Treatment with MA, however, was able to modulate the autophagic markers (e.g. Beclin-1, p62, TRAF6, and LC3) in the gastrocnemius and in the hearts of tumour-bearing rats. Most importantly, 100 mg/kg/day MA reduced mortality [hazard ratio (HR): 0.44; 95%CI: 0.20-1.00; P = 0.0486]. CONCLUSIONS: Megestrol acetate improved survival and reduced wasting through a marked downregulation of autophagy, occurring in both skeletal and heart muscle, the latter effect leading to a significant improvement of cardiac function. Our data suggest that MA might represent a valuable strategy to counteract the development of cancer cachexia-induced cardiomyopathy.

Distribution and function of biogenic amines in the heart of Nautilus pompilius L. (Cephalopoda, Tetrabranchiata).

Biogenic amines (serotonin and catecholamines), play an important role in the control of the blood flow not only in vertebrates, but also in invertebrates such as cephalopods. In contrast to the well investigated hearts of the a 'modern', coleoid cephalopods, the innervation of the heart of the archaic Nautilus pompilius L. has not been studied in detail. In this study the distribution and effects of biogenic amines in the Nautilus heart were investigated. Serotonin and catecholamines were visualised by the glyxoylic acid induced fluorescence. High performance liquid chromatotography analysis was performed to discriminate between the catecholamines, which showed a high content of noradrenaline in the 4 auricles, the aorta and the ventricle, whereas the ventricle showed a high dopamine content. Adrenaline was found at a very low concentration in the ventricle. Serotonin and dopamine were also immunohistochemically localised to larger nerves and throughout the heart, respectively. In organ bath experiments, the auricles showed little spontaneous activity. After adding serotonin, they displayed rhythmical contractions, which were accelerated dose-dependently by noradrenaline. In summary, these data suggest an important role for biogenic amines in the control of the heart of Nautilus pompilius L., with serotonin possibly stimulating excitatory nerve fibres, whereas noradrenaline is likely to influence the muscle contraction itself.

Febuxostat improves outcome in a rat model of cancer cachexia.

BACKGROUND: Activity of xanthine oxidase is induced in cancer cachexia, and its inhibition by allopurinol or oxypurinol improves survival and reduces wasting in the Yoshida hepatoma cancer cachexia model. Here, we tested the effects of the second-generation xanthine oxidase inhibitor febuxostat compared with placebo in the same model as used previously by our group. METHODS: Wistar rats (~200 g) were treated daily with febuxostat at 5 mg/kg/day or placebo via gavage for a maximum of 17 days. Weight change, quality of life, and body composition were analysed. After sacrifice, proteasome activity in the gastrocnemius muscle was measured. Muscle-specific proteins involved in metabolism were analysed by western blotting. RESULTS: Treatment of the tumour-bearing rats with febuxostat led to a significantly improved survival compared with placebo (hazard ratio: 0.45, 95% confidence interval: 0.22-0.93, P = 0.03). Loss of body weight was reduced (-26.3 ± 12.4 g) compared with placebo (-50.2 ± 2.1 g, P < 0.01). Wasting of lean mass was attenuated (-12.7 ± 10.8 g) vs. placebo (-31.9 ± 2.1 g, P < 0.05). While we did not see an effect of febuxostat on proteasome activity at the end of the study, the pAkt/Akt ratio was improved by febuxostat (0.94 ± 0.09) vs. placebo (0.41 ± 0.05, P < 0.01), suggesting an increase in protein synthesis. CONCLUSIONS: Febuxostat attenuated cachexia progression and improved survival of tumour-bearing rats.

Influence of cancer cachexia on drug liver metabolism and renal elimination in rats.

BACKGROUND: Body wasting and cachexia change body composition and organ function, with effects on drug pharmacokinetics. The aim of this study was to investigate how cancer and cancer cachexia modify liver metabolism and renal drug elimination in rats. METHODS: Nine male Wistar-Han rats received a single oral dose of midazolam and propranolol (markers of hepatic metabolism), and 10 rats received single intravenous dose of iohexol, a marker of glomerular filtration rate. After drug delivery, multiple dried blood samples were obtained within 2 h post-dose to evaluate drug pharmacokinetic profiles. After baseline sampling (D0), rats were injected with tumour cells. Drug application and blood sampling were repeated when rats developed tumours (Day 5-D5), and when rats were severely cachectic (Day 10-D10). Clearance (CL) and volume of distribution (Vd) of drugs were assessed with non-linear mixed effects modelling. Weight and body composition were measured on D0 and D10 and were related to pharmacokinetic parameters. RESULTS: All three drugs showed non-significant trend towards increased CL and Vd on D5. On D10, midazolam and propranolol CL and midazolam Vd significantly decreased from baseline (-80.5%, -79.8%, and -72.0%, respectively, P < 0.05 for all). Iohexol CL decreased by 29.8% from baseline value on D10, which was related to body weight loss (Pearson's r = 0.837, P = 0.019). CONCLUSIONS: Hepatic metabolism and renal drug elimination are significantly reduced in cachexia, which could increase risk of dose-related adverse events.

Muscle wasting: an overview of recent developments in basic research.

The syndrome of cachexia, i.e., involuntary weight loss in patients with underlying diseases, sarcopenia, i.e., loss of muscle mass due to aging, and general muscle atrophy from disuse and/or prolonged bed rest have received more attention over the last decades. All lead to a higher morbidity and mortality in patients, and therefore, they represent a major socio-economic burden for the society today. This mini-review looks at recent developments in basic research that are relevant to the loss of skeletal muscle. It aims to cover the most significant publication of last 3 years on the causes and effects of muscle wasting, new targets for therapy development, and potential biomarkers for assessing skeletal muscle mass. The targets include the following: (1) E-3 ligases TRIM32, SOCS1, and SOCS3 by involving the elongin BC ubiquitin-ligase, Cbl-b, culling 7, Fbxo40, MG53 (TRIM72), and the mitochondrial Mul1; (2) the kinase MST1; and (3) the G-protein Gαi2. D(3)-creatine has the potential to be used as a novel biomarker that allows to monitor actual change in skeletal muscle mass over time. In conclusion, significant development efforts are being made by academic groups as well as numerous pharmaceutical companies to identify new target and biomarker muscles, as muscle wasting represents a great medical need, but no therapies have been approved in the last decades.

Muscle wasting: an overview of recent developments in basic research.

The syndrome of cachexia, i.e. involuntary weight loss in patients with underlying diseases, sarcopenia, i.e. loss of muscle mass due to ageing, and general muscle atrophy from disuse and/or prolonged bed rest have received more attention over the last decades. All lead to a higher morbidity and mortality in patients and therefore, they represent a major socio-economic burden for the society today. This mini-review looks at recent developments in basic research that are relevant to the loss of skeletal muscle. It aims to cover the most significant publication of last three years on the causes and effects of muscle wasting, new targets for therapy development and potential biomarkers for assessing skeletal muscle mass. The targets include 1) E-3 ligases: TRIM32, SOCS1 and SOCS3 by involving the elongin BC ubiquitin-ligase, Cbl-b, culling 7, Fbxo40, MG53 (TRIM72) and the mitochondrial Mul1, 2) the kinase MST1 and 3) the G-protein Gαi2. D(3)-creatine has the potential to be used as a novel biomarker that allows to monitor actual change in skeletal muscle mass over time. In conclusion, significant development efforts are being made by academic groups as well as numerous pharmaceutical companies to identify new targets and biomarkers muscle, as muscle wasting represents a great medical need, but no therapies have been approved in the last decades.

Six1 is down-regulated in end-stage human dilated cardiomyopathy independently of Ezh2.

BACKGROUND: Recently, it was shown that a knock-out (KO) of the polycomb histone methyltransferase Ezh2 leads to cardiac hypertrophy in mice, which was driven by the homeodomain transcription factor Six1. Here, we analyzed the expression of Six1 and its regulating factor Ezh2 in cardiac tissue of patients with end-stage dilative cardiomyopathy (DCM). METHODS: Tissue samples of patients with end-stage DCM (n = 35) were compared with controls (n = 12) for the protein expression of Ezh1, Ezh2, Six1, and a marker of protein expression p70S6K. RESULTS: Contrary to the Ezh2-KO mouse model, we found a down-regulation of Six1 (26%) and an up-regulation of Ezh2 (76%) in DCM hearts, (both P < 0.05). Expression of Ezh2 and Six1 did not correlate in human tissue (DCM: r2: 0.03, P = 0.31 and donor: r2: 0.05, P = 0.45). Expression of Six1 weakly correlated with left ventricular end-systolic diameter and fractional shortening. In DCM, Six1 also showed a positive correlation to the expression of the ribosomal protein p70S6K (r: 0.39, P = 0.029), which is involved in protein synthesis. This correlation was not seen in donor tissue, which showed a trend for a negative correlation (r: -0.49, P = 0.08). CONCLUSION: Our data indicate that the Ezh2/Six1 axis might be involved in human DCM. However, Six1 expression may be regulated by factors other than Ezh2, and more research is needed to determine the precise role of Ezh2/Six1 in human DCM.

The anabolic catabolic transforming agent (ACTA) espindolol increases muscle mass and decreases fat mass in old rats.

BACKGROUND: Sarcopenia, the age-related, progressive loss of skeletal muscle mass, strength, and function, is a considerable socioeconomic burden by increasing risks of falls, fractures, and frailty. Moreover, sarcopenic patients are often obese and therapeutic options are very limited. METHODS: Here, we assessed the efficacy of espindolol on muscle mass in 19-month-old male Wistar Han rats (weight, 555 ± 18 g), including safety issues. Rats were randomized to treatment with 3 mg/kg/day espindolol (n = 8) or placebo (n = 14) for 31 days. RESULTS: Placebo-treated rats progressively lost body weight (-15.5 ± 7.2 g), lean mass (-1.5 ± 4.2 g), and fat mass (-15.6 ± 2.7 g), while espindolol treatment increased body weight (+8.0 ± 6.1 g, p < 0.05), particularly lean mass (+43.4 ± 3.5 g, p < 0.001), and reduced fat mass further (-38.6 ± 3.4 g, p < 0.001). Anabolic/catabolic signaling was assessed in gastrocnemius muscle. Espindolol decreased proteasome and caspase-3 proteolytic activities by approximately 50 % (all p < 0.05). Western blotting showed a reduced expression of key catabolic regulators, including NFκB, MuRF1, and LC-3 (all p < 0.01). The 50- and 26-kDa forms of myostatin were downregulated fivefold and 20-fold, respectively (both p < 0.001). Moreover, 4E-BP-1 was reduced fivefold (p < 0.01), while phospho-PI3K was upregulated fivefold (p < 0.001), although Akt expression and phosphorylation were lower compared to placebo (all p < 0.05). No regulation of p38 and expression of ERK1/2 were observed, while phosphorylation of p38 was reduced (-54 %, p < 0.001) and ERK1/2 was increased (115 and 83 %, respectively, both p < 0.01). Espindolol did not affect cardiac function (echocardiography) or clinical plasma parameters. CONCLUSION: Espindolol reversed the effects of aging/sarcopenia, particularly loss of muscle mass and increased fat mass. Thus, espindolol is an attractive candidate drug for the treatment of sarcopenia patients.

Rosiglitazone reduces body wasting and improves survival in a rat model of cancer cachexia.

OBJECTIVE: Rosiglitazone improves insulin sensitivity and promotes weight gain in patients with type 2 diabetes mellitus, which could be useful in wasting and cachexia. However, its effects on cardiac function are controversial. The aim of this study was to investigate the effects of rosiglitazone on body wasting, body composition, cardiac function, and survival in a rat model of cancer cachexia. METHODS: Rats were injected with Yoshida AH-130 hepatoma tumor cells and randomized to receive placebo or rosiglitazone 4 mg/kg daily. Treatment started 1 d after tumor inoculation and the rats were sacrificed 14 d thereafter. Body weight and body composition was measured at baseline and after removal of tumor. Echocardiography was performed at baseline and on day 11. At the end of the study, organs were weighed and the proteasome activity in gastrocnemius muscle was measured. RESULTS: Survival analysis showed a significant benefit from treatment with rosiglitazone (hazard ratio = 0.38, 95% confidence interval: 0.15-0.86). Rosiglitazone reduced average daily weight loss (2.33 g/d rosiglitazone versus 3.93 g/d placebo; P < 0.05) as a result of both fat and lean mass preservation. It decelerated white and brown tissue wasting, but had no effect on skeletal muscle mass and heart mass. However, peptidyl-glutamyl-protein-hydrolysing and trypsin-like activity in gastrocnemius muscle was significantly reduced by rosiglitazone. Finally, it increased left ventricular ejection fraction, fractional shortening, and systolic volume and improved cardiac output in cachectic cancer rats. CONCLUSIONS: Rosiglitazone prevents weight loss and improves survival in a rat model of cancer cachexia. It exerts beneficial effects on cardiac function.