Anticytokine treatment prevents the increase in the activity of ATP-ubiquitin- and Ca(2+)-dependent proteolytic systems in the muscle of tumour-bearing rats

The ascites hepatoma Yoshida AH-130 induces loss of body weight and tissue waste. Tumour necrosis factor alpha (TNF-alpha) plays a pivotal role in the pathogenesis of muscle wasting in this model system, but other cytokines, such as interleukin-6, may be involved.In order to verify whether a combined anticytokine treatment may synergistically counteract muscle protein degradation, tumour bearing rats were treated with pentoxyfilline (PTX, an inhibitor of TNF-alpha synthesis), or with suramin (SUR, an antiprotozoal drug blocking the peripheral action of several cytokines including IL-6 and TNF-alpha), or both the drugs, and the effects on muscle proteolytic systems were assessed.Muscle protein loss in the AH-130-bearing rats was associated with increased activity of both the ATP-ubiquitin- and the calpain- dependent proteolytic pathways (246% and 230% of controls, respectively). Both PTX and SUR, either alone or in combination, prevented the depletion of muscle mass and significantly reduced the activity of muscle proteolytic systems. In particular, treatment with SUR, either alone or with PTX, induced a decrease in enzymatic activities to values similar to those of controls. The results obtained in the present paper demonstrate that: (i) muscle depletion in this model is indeed associated with increased proteasome- and calpain-dependent proteolysis, as previously suggested by increased mRNA expression of molecules pertaining to both pathways; (ii) anticytokine treatments effectively reduce muscle protein loss by down-regulating the activity of at least two major proteolitic systems; (iii) SUR is more effective than PTX in reducing the activity of proteolytic systems, possibly because of its multiple anticytokine action.     

Increased muscle ubiquitin mRNA levels in gastric cancer patients

The intramuscular ATP-dependent ubiquitin (Ub)-proteasome proteolytic system is hyperactivated in experimental cancer cachexia. The present study aimed at verifying whether the expression of the muscle Ub mRNA is altered in patients with cancer. Total muscle RNA was extracted using the guanidinium isothiocyanate/phenol/chloroform method from rectus abdominis biopsies obtained intraoperatively from 20 gastric cancer (GC) patients and 10 subjects with benign abdominal diseases (CON) undergoing surgery. Ub mRNA levels were measured by northern blot analysis. Serum soluble tumor necrosis factor receptor (sTNFR) was measured by ELISA. Ub mRNA levels (arbitrary units, means +/- SD) were 2,345 +/- 195 in GC and 1,162 +/- 132 in CON (P = 0.0005). Ub mRNA levels directly correlated with disease stage (r = 0.608, P = 0.005), being 1,945 +/- 786 in stages I and II, 2,480 +/- 650 in stage III, and 3,799 +/- 66 in stage IV. Ub mRNA and sTNFR did not correlate with age and nutritional parameters. This study confirms experimental data indicating an overexpression of muscle Ub mRNA in cancer cachexia. Lack of correlation with nutritional status suggests that Ub activation in human cancer is an early feature that precedes any clinical sign of cachexia.     

Improving inhaler adherence in patients with Chronic Obstructive Pulmonary Disease: a cost-effectiveness analysis

Background

The PHARMACOP-intervention significantly improved medication adherence and inhalation technique for patients with COPD compared with usual care. This study aimed to evaluate its cost-effectiveness.

Methods

An economic analysis was performed from the Belgian healthcare payer’s perspective. A Markov model was constructed in which a representative group of patients with COPD (mean age of 70 years, 66% male, 43% current smokers and mean Forced Expiratory Volume in 1 second of % predicted of 50), was followed for either receiving the 3-month PHARMACOP-intervention or usual care. Three types of costs were calculated: intervention costs, medication costs and exacerbation costs. Outcome measures included the number of hospital-treated exacerbations, cost per prevented hospital-treated exacerbation and cost per Quality Adjusted Life-Year. Follow-up was 1 year in the basecase analysis. Sensitivity and scenario analyses (including long-term follow-up) were performed to assess uncertainty.

Results

In the basecase analysis, the average overall costs per patient for the PHARMACOP-intervention and usual care were €2,221 and €2,448, respectively within the 1-year time horizon. This reflects cost savings of €227 for the PHARMACOP-intervention. The PHARMACOP-intervention resulted in the prevention of 0.07 hospital-treated exacerbations per patient (0.177 for PHARMACOP versus 0.244 for usual care). Results showed robust cost-savings in various sensitivity analyses.

Conclusions

Optimization of current pharmacotherapy (e.g. close monitoring of inhalation technique and medication adherence) has been shown to be cost-saving and should be considered before adding new therapies.     

Biologically relevant effects of mRNA amplification on gene expression profiles

Background  

Gene expression microarray technology permits the analysis of global gene expression profiles. The amount of sample needed limits the use of small excision biopsies and/or needle biopsies from human or animal tissues. Linear amplification techniques have been developed to increase the amount of sample derived cDNA. These amplified samples can be hybridised on microarrays. However, little information is available whether microarrays based on amplified and unamplified material yield comparable results.     

Skeletal muscle apoptosis is not increased in gastric cancer patients with mild-moderate weight loss

Numerous experimental and clinical studies have shown that skeletal muscle apoptotis may increase in wasting conditions and suggest that apoptosis might contribute to the loss of lean body mass. Data in cancer patients are still lacking. The present study aimed at verifying whether apoptosis was enhanced in the skeletal muscle of 16 patients with gastric cancer with respect to controls. A biopsy specimen was obtained from the rectus abdominis muscle. The occurrence of apoptosis in muscle biopsies was determined morphologically by the fluorescent transferase-mediated dUTP nick end labeling assay and by immunohistochemistry for caspase-3 and caspase-1. Mean weight loss was 6+/-2% in cancer patients and 0.5+/-0.1% in controls (p<0.0001). Serum albumin levels (g/dL) were 3.7+/-0.3 in cancer patients and 4.1+/-0.2 in controls (p<0.05). The percentage of apoptotic myonuclei was similar in cancer patients and in controls (1.5+/-0.3 versus 1.4+/-0.2, respectively; p=ns), in gastric cancer patients with mild (1.6+/-0.4) or moderate-severe weight loss (1.4+/-0.5) (p=ns), and in the different stages of disease (stages I-II: 1.5+/-0.7; stage III: 1.3+/-0.4; stage IV: 1.6+/-0.3; p=ns). By immunohistochemistry, caspase-1 and caspase-3 positive fibers were absent in controls and in neoplastic patients. Poly-ADP-ribosyl polymerase, a typical caspase-3 substrate whose processing is indicative of caspase-3 activation, was not cleaved in muscle biopsies of cancer patients. These data suggest that skeletal muscle apoptosis is not increased in neoplastic patients with mild-moderate weight loss and argue against the hypotheses that caspase-3 activation might be an essential step of myofibrillar proteolysis in cancer-related muscle wasting.     

Chromosome phylogeny of the subfamily Pitheciinae (Platyrrhini,Primates) by classic cytogenetics and chromosome painting

Background  

The New World monkey (Platyrrhini) subfamily Pitheciinae is represented by the genera Pithecia, Chiropotes and Cacajao. In this work we studied the karyotypes of Pithecia irrorata (2n = 48) and Cacajao calvus rubicundus (2n = 45 in males and 2n = 46 in females) by G- and C-banding, NOR staining and chromosome painting using human and Saguinus oedipus whole chromosome probes. The karyotypes of both species were compared with each other and with Chiropotes utahicki (2n = 54) from the literature.     

Direct anti-metastatic efficacy by the DNA enzyme Dz13 and downregulated MMP-2, MMP-9 and MT1-MMP in tumours

The DNA enzyme Dz13, targeted against the oncogene c-Jun, is capable of inhibiting various model tumours in mice albeit in ectopic models of neoplasia. In previous studies using orthotopic models of disease, the inhibitory effects of Dz13 on secondary growth was a direct result of growth inhibition at the primary lesion site. Thus, the direct and genuine effects on metastasis were not gauged. In this study, Dz13 was able to inhibit both locoregional and distal metastasis of tumour cells in mice, in studies where the primary tumours were unaffected due to the late and clinically-mimicking nature of treatment commencement. In addition, the effect of Dz13 against tumours has now been extended to encompass breast and prostate cancer. Dz13 upregulated the matrix metalloproteinase (MMP)-2 and MMP-9, and decreased expression of MT1-MMP (MMP-14) in cultured tumour cells. However, in sections of ectopic tumours treated with Dz13, both MMP-2 and MMP-9 were downregulated. Thus, not only is Dz13 able to inhibit tumour growth at the primary site, but also able to decrease the ability of neoplastic cells to metastasise. These findings further highlight the growing potential of Dz13 as an antineoplastic agent.     

Are antioxidants useful for treating skeletal muscle atrophy?

Changes in the skeletal muscle protein mass frequently occur in both physiological and pathological states. Muscle hypotrophy, in particular, is commonly observed during aging and is characteristic of several pathological conditions such as neurological diseases, cancer, diabetes, and sepsis. The skeletal muscle protein content depends on the relative rates of synthesis and degradation, which must be coordinately regulated to maintain the equilibrium. Pathological muscle depletion is characterized by a negative nitrogen balance, which results from disruption of this equilibrium due to reduced synthesis, increased breakdown, or both. The current view, mainly based on experimental data, considers hypercatabolism as the major cause of muscle protein depletion. Several signaling pathways that probably contribute to muscle atrophy have been identified, and there is increasing evidence that oxidative stress, due to reactive oxygen species production overwhelming the intracellular antioxidant systems, plays a role in causing muscle depletion both during aging and in chronic pathological states. In particular, oxidative stress has been proposed to enhance protein breakdown, directly or by interacting with other factors. This review focuses on the possibility of using antioxidant treatments to target molecular pathways involved in the pathogenesis of skeletal muscle wasting.     

Changes induced by fasting and cycloheximide in the vacuolar apparatus of rat hepatocytes. A morphometric investigation

An increase in the number of autophagic vacuoles and in the size of the dense and residual bodies was observed in the hepatocytes of rats fasted for 24 hours; moreover, the number of dense bodies was reduced. These data suggest that the previously reported acceleration in cell protein degradation caused by fasting can be accounted for by enhanced autography. The treatment with cycloheximide, which was previously found to prevent this proteolytic response, also prevents the appearance of signs of enhanced autophagic activity.