Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0006625 (cachexia)
 5,650 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a primary malignant mixed mesodermal tumor in the right ovary of 75-year-old woman. She was admitted to Kobe West Municipal Hospital because of an abdominal fullness and an upper abdominal pain. A laparotomy yielded yellowish-clear ascites (2,000 ml) a tumor located in the right ovary, an upper abdominal mass the size of a child's head between the stomach and the transverse colon, and disseminating small tumors of the peritoneum. The left ovary and uterus showed no particular change. Four months after the onset of her symptoms, the patient died of carcinomatous cachexia and dyspnea. On microscope examination, the tumor of right ovary showed combined features of an adenocarcinoma, an adenosquamous carcinoma and a serous cystadenocarcinoma with foci of a heterologous stromal differentiation, that is an area of immature, striated muscle cells, bone, and cartilage and undifferentiated spindle cells. Immunohistochemical stains were useful for determining elements of the tumor cells. Epithelial tumor cells were positive for cytokeratin, epithelial membrane antigen, and CEA, while mesenchymal tumor cells were generally positive for vimentin and the immature muscle cells were especially positive for desmin, actin, and myosin. Additionally, myoglobin was identified in the rhabdomyoblast. Finally, S-100 protein was present in cartilage area and partially present in the adenocarcinomatous element.
 ...
PMID:[A malignant mixed mesodermal tumor of the ovary]. 217 88

Muscle wasting is a critical feature of patients afflicted by AIDS or cancer. In a murine model of muscle wasting, tumor necrosis factor alpha (TNF alpha) induces oxidative stress and nitric oxide synthase (NOS) in skeletal muscle, leading to decreased myosin creatinine phosphokinase (MCK) expression and binding activities. The impaired MCK-E box binding activities resulted from abnormal myogenin-Jun-D complexes, and were normalized by the addition of Jun-D, dithiothreitol or Ref-1, a nuclear redox protein. Treatment of skeletal muscle cells with a phorbol ester, a superoxide-generating system, an NO donor or a Jun-D antisense oligonucleotide decreased Jun-D activity and transcription from the MCK-E box, which were prevented by antioxidants, a scavenger of reducing equivalents, a NOS inhibitor and/or overexpression of Jun-D. The decreased body weight, muscle wasting and skeletal muscle molecular abnormalities of cachexia were prevented by treatment of TNF alpha mice with the antioxidants D-alpha-tocopherol of BW755c, or the NOS inhibitor nitro-L-arginine.
 ...
PMID:Muscle wasting and dedifferentiation induced by oxidative stress in a murine model of cachexia is prevented by inhibitors of nitric oxide synthesis and antioxidants. 861 20

The diaphragm as a striated muscle is characterized by the repetition of a single element arranged in series: the sarcomere containing two kinds of myofilaments: a thick one constituted by the myosin, and a thin one primarily composed of actin. The myosin molecule consists of two heads where two myosin heavy chains (MHC) are fixed, a flexible hinge with two light (MLC) chains, and long rod-shaped tails. The diaphragm contains 4 MHC isoforms (MHC-slow, MHC-2A, MHC-2B, MHC-2X) and 6 MLC isoforms (MLC-1f, MLC-3f, MLC-1sa, MLC-1sb, MLC-2f, MLC-2s/v). In humans, the diaphragm contains mainly fibers expressing the isoforms MHC-slow, MHC-2A, and MLC-2f, MLC-2s et MLC-1f. For the mechanical properties of the different isoforms, there is a gradient from the MHC-slow to the MHC-2A, MHC-2B and MHC-2X/2B. According to the circumstances, the diaphragm will adapt towards a slow profile (COPD, cardiac failure and in animals: Duchenne muscular dystrophy, denervation-1 week, age-female, corticosteroids, chronic stimulation), or a fast profile (in animals: chronic hypoxia, denervation-2 weeks, age-males) or a more oxidative profile (in animals: cachexia, obesity). The reasons why the diaphragm adapts towards a slower or a faster muscle are not known. In fact, for a given pathological situation, several factors are able to influence the fiber composition of the diaphragm. Therefore, the net result of the influence of these different factors in terms of MHC and MLC diaphragm adaptation is difficult to predict.
 ...
PMID:[Clinical relevance of myosin isoforms in the diaphragm]. 1093 18

Cancer cachexia is characterized by selective depletion of skeletal muscle protein reserves. Soleus muscles from mice bearing a cachexia-inducing tumor (MAC16) showed an increased protein degradation in vitro, as measured by tyrosine release, when compared with muscles from nontumor-bearing animals. After incubation under conditions that modify different proteolytic systems, lysosomal, calcium-dependent, and ATP-dependent proteolysis were found to contribute to the elevated protein catabolism. Treatment of mice bearing the MAC16 tumor with the polyunsaturated fatty acid, eicosapentaenoic acid (EPA), attenuated loss of body weight and significantly suppressed protein catabolism in soleus muscles through an inhibition of an ATP-dependent proteolytic pathway. The ATP-ubiquitin-dependent proteolytic pathway is considered to play a major role in muscle catabolism in cachexia, and functional proteasome activity, as determined by "chymotrypsin-like" enzyme activity, was significantly elevated in gastrocnemius muscle of mice bearing the MAC16 tumor as weight loss progressed. When animals bearing the MAC16 tumor were treated with EPA, functional proteasome activity was completely suppressed, together with attenuation of the expression of 20S proteasome alpha-subunits and the p42 regulator, whereas there was no effect on the expression of the ubiquitin-conjugating enzyme (E2(14k)). These results suggest that EPA induces an attenuation of the up-regulation of proteasome expression in cachectic mice, and this was correlated with an increase in myosin expression, confirming retention of contractile proteins. EPA also inhibited growth of the MAC16 tumor in a dose-dependent manner, and this correlated with suppression of the expression of the 20S proteasome alpha-subunits in tumor cells, suggesting that this may be the mechanism of tumor growth inhibition. Thus EPA antagonizes loss of skeletal muscle proteins in cancer cachexia by down-regulation of proteasome expression, and this may also be the mechanism for inhibition of tumor growth.
 ...
PMID:Mechanism of attenuation of skeletal muscle protein catabolism in cancer cachexia by eicosapentaenoic acid. 1132 28

Muscle wasting in cancer cachexia is associated with increased levels of malondialdehyde (MDA) in gastrocnemius muscles, suggesting an increased oxidative stress. To determine whether oxidative stress contributes to muscle protein catabolism, an in vitro model system, consisting of C2C12 myotubes, was treated with either 0.2 mM FeSO4, 0.1 mM H2O2, or both, to replicate the rise in MDA content in cachexia. All treatments caused an increased protein catabolism and a decreased myosin expression. There was an increase in the proteasome chymotrypsin-like enzyme activity, while immunoblotting showed an increased expression of the 20S proteasome alpha-subunits, p42, and the ubiquitin-conjugating enzyme, E214k. These results show that mild oxidative stress increases protein degradation in skeletal muscle by causing an increased expression of the major components of the ubiquitin-proteasome pathway.
 ...
PMID:Induction of protein catabolism and the ubiquitin-proteasome pathway by mild oxidative stress. 1191 72

The mechanism of muscle protein catabolism induced by proteolysis-inducing factor, produced by cachexia-inducing murine and human tumours has been studied in vitro using C(2)C(12) myoblasts and myotubes. In both myoblasts and myotubes protein degradation was enhanced by proteolysis-inducing factor after 24 h incubation. In myoblasts this followed a bell-shaped dose-response curve with maximal effects at a proteolysis-inducing factor concentration between 2 and 4 nM, while in myotubes increased protein degradation was seen at all concentrations of proteolysis-inducing factor up to 10 nM, again with a maximum of 4 nM proteolysis-inducing factor. Protein degradation induced by proteolysis-inducing factor was completely attenuated in the presence of cycloheximide (1 microM), suggesting a requirement for new protein synthesis. In both myoblasts and myotubes protein degradation was accompanied by an increased expression of the alpha-type subunits of the 20S proteasome as well as functional activity of the proteasome, as determined by the 'chymotrypsin-like' enzyme activity. There was also an increased expression of the 19S regulatory complex as well as the ubiquitin-conjugating enzyme (E2(14k)), and in myotubes a decrease in myosin expression was seen with increasing concentrations of proteolysis-inducing factor. These results show that proteolysis-inducing factor co-ordinately upregulates both ubiquitin conjugation and proteasome activity in both myoblasts and myotubes and may play an important role in the muscle wasting seen in cancer cachexia.
 ...
PMID:Development of an in-vitro model system to investigate the mechanism of muscle protein catabolism induced by proteolysis-inducing factor. 1208 14

Cachexia is commonly seen in cancer and is characterized by severe muscle wasting, but little is known about the effect of cancer cachexia on expression of contractile protein isoforms such as myosin. Other causes of muscle atrophy shift expression of myosin isoforms toward increased fast (type II) isoform expression. We injected mice with murine C-26 adenocarcinoma cells, a tumor cell line that has been shown to cause muscle wasting. Mice were killed 21 days after tumor injection, and hindlimb muscles were removed. Myosin heavy chain (MHC) and myosin light chain (MLC) content was determined in muscle homogenates by SDS-PAGE. Body weight was significantly lower in tumor-bearing (T) mice. There was a significant decrease in muscle mass in all three muscles tested compared with control, with the largest decrease occurring in the soleus. Although no type IIb MHC was detected in the soleus samples from control mice, type IIb comprised 19% of the total MHC in T soleus. Type I MHC was significantly decreased in T vs. control soleus muscle. MHC isoform content was not significantly different from control in plantaris and gastrocnemius muscles. These data are the first to show a change in myosin isoform expression accompanying muscle atrophy during cancer cachexia.
 ...
PMID:Altered expression of skeletal muscle myosin isoforms in cancer cachexia. 1237 98

Cachexia is a syndrome characterized by wasting of skeletal muscle and contributes to nearly one-third of all cancer deaths. Cytokines and tumor factors mediate wasting by suppressing muscle gene products, but exactly which products are targeted by these cachectic factors is not well understood. Because of their functional relevance to muscle architecture, such targets are presumed to represent myofibrillar proteins, but whether these proteins are regulated in a general or a selective manner is also unclear. Here we demonstrate, using in vitro and in vivo models of muscle wasting, that cachectic factors are remarkably selective in targeting myosin heavy chain. In myotubes and mouse muscles, TNF-alpha plus IFN-gamma strongly reduced myosin expression through an RNA-dependent mechanism. Likewise, colon-26 tumors in mice caused the selective reduction of this myofibrillar protein, and this reduction correlated with wasting. Under these conditions, however, loss of myosin was associated with the ubiquitin-dependent proteasome pathway, which suggests that mechanisms used to regulate the expression of muscle proteins may be cachectic factor specific. These results shed new light on cancer cachexia by revealing that wasting does not result from a general downregulation of muscle proteins but rather is highly selective as to which proteins are targeted during the wasting state.
 ...
PMID:Cancer cachexia is regulated by selective targeting of skeletal muscle gene products. 1528 3

The potential for inhibitors of nuclear factor-kappaB (NF-kappaB) activation to act as inhibitors of muscle protein degradation in cancer cachexia has been evaluated both in vitro and in vivo. Activation of NF-kappaB is important in the induction of proteasome expression and protein degradation by the tumour factor, proteolysis-inducing factor (PIF), since the cell permeable NF-kappaB inhibitor SN50 (18 microM) attenuated the expression of 20S proteasome alpha-subunits, two subunits of the 19S regulator MSS1 and p42, and the ubiquitin-conjugating enzyme, E2(14k), as well as the decrease in myosin expression in murine myotubes. To assess the potential therapeutic benefit of NF-kappaB inhibitors on muscle atrophy in cancer cachexia, two potential inhibitors were employed; curcumin (50 microM) and resveratrol (30 microM). Both agents completely attenuated total protein degradation in murine myotubes at all concentrations of PIF, and attenuated the PIF-induced increase in expression of the ubiquitin-proteasome proteolytic pathway, as determined by the 'chymotrypsin-like' enzyme activity, proteasome subunits and E2(14k). However, curcumin (150 and 300 mg kg(-1)) was ineffective in preventing weight loss and muscle protein degradation in mice bearing the MAC16 tumour, whereas resveratrol (1 mg kg(-1)) significantly attenuated weight loss and protein degradation in skeletal muscle, and produced a significant reduction in NF-kappaB DNA-binding activity. The inactivity of curcumin was probably due to a low bioavailability. These results suggest that agents which inhibit nuclear translocation of NF-kappaB may prove useful for the treatment of muscle wasting in cancer cachexia.
 ...
PMID:Induction of proteasome expression in skeletal muscle is attenuated by inhibitors of NF-kappaB activation. 1547 67

Loss of skeletal muscle in cancer cachexia has a negative effect on both morbidity and mortality. The role of nuclear factor-kappaB (NF-kappaB) in regulating muscle protein degradation and expression of the ubiquitin-proteasome proteolytic pathway in response to a tumour cachectic factor, proteolysis-inducing factor (PIF), has been studied by creating stable, transdominant-negative, muscle cell lines. Murine C(2)C(12) myoblasts were transfected with plasmids with a CMV promoter that had mutations at the serine phosphorylation sites required for degradation of I-kappaBalpha, an NF-kappaB inhibitory protein, and allowed to differentiate into myotubes. Proteolysis-inducing factor induced degradation of I-kappaBalpha, nuclear accumulation of NF-kappaB and an increase in luciferase reporter gene activity in myotubes containing wild-type, but not mutant, I-kappaBalpha proteins. Proteolysis-inducing factor also induced total protein degradation and loss of the myofibrillar protein myosin in myotubes containing wild-type, but not mutant, plasmids at the same concentrations as those causing activation of NF-kappaB. Proteolysis-inducing factor also induced increased expression of the ubiquitin-proteasome pathway, as determined by 'chymotrypsin-like' enzyme activity, the predominant proteolytic activity of the beta-subunits of the proteasome, protein expression of 20S alpha-subunits and the 19S subunits MSS1 and p42, as well as the ubiquitin conjugating enzyme, E2(14k), in cells containing wild-type, but not mutant, I-kappaBalpha. The ability of mutant I-kappaBalpha to inhibit PIF-induced protein degradation, as well as expression of the ubiquitin-proteasome pathway, confirms that both of these responses depend on initiation of transcription by NF-kappaB.
 ...
PMID:NF-kappaB mediates proteolysis-inducing factor induced protein degradation and expression of the ubiquitin-proteasome system in skeletal muscle. 1571 7


1 2 3 Next >>