Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0235394 (wasting)
 8,040 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transgenic mice aberrantly expressing the granulocyte-macrophage colony stimulating factor (GM-CSF) gene develop an unusual syndrome of blindness, tissue damage and wasting which is associated with accumulations of hemopoietic cells. In order to further characterize this disease state, we have used messenger RNA detection techniques to show that the genes for tumor necrosis factor (TNF alpha), interleukin-1 alpha (IL-1 alpha) and basic fibroblast growth factor (bFGF) are expressed at abnormally high levels in both macrophages and granulocytes in transgenic mice. Furthermore, since these cell types also express the GM-CSF transgene, it is likely that they are autocrine stimulated by GM-CSF. These observations raise the possibilities that, first, the expression of tumor necrosis factor alpha, interleukin-1 alpha and basic fibroblast growth factor in hemopoietic cells is a direct consequence of their autostimulation by GM-CSF, and second, that these cytokines may be responsible for some aspects of the transgenic mouse disease.
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PMID:TNF alpha, IL-1 alpha and bFGF are implicated in the complex disease of GM-CSF transgenic mice. 158 89

Early wasting and subsequent mortality may occur in mice of some inbred strains following infection with Trypanosoma cruzi. It was hypothesized that TNF alpha/cachectin might be involved in this process. Thus, sera collected from mice of strains differing in their susceptibility or resistance to Trypanosoma cruzi infection were checked for the presence and level of TNF alpha, a cytokine able to exert acute toxic effects. C3H/HeJ or C3H/HePas (susceptible), BALB/c (intermediate) and C57BL/6 (resistant) mice were infected with the CL or Colombian strain of Trypanosoma cruzi, and TNF activity was measured in the sera during the acute phase of the infection. Only serum collected from infected C3H/He mice contained TNF activity. However, TNF activity could be measured in serum of all strains, following LPS infection, indicating that the infection was able to prime macrophages of infected mice to secrete TNF alpha. The TNF alpha/cachectin release in the sera of C3H mice may play a role in the early wasting and death of these mice after Trypanosoma cruzi infection.
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PMID:Is TNF alpha involved in early susceptibility of Trypanosoma cruzi-infected C3H/He mice? 190 50

In the paper the possible physiological significance and pathological role of cachectin as a mediator of endotoxic shock and wasting in chronic diseases are reviewed. The influence of this monokine on normal haematopoietic cells and their leukaemic counterparts is presented. The effect of TNF on neoplastic cells in vitro and in vivo and its possible application in the treatment of cancer is also discussed.
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PMID:[Biological characteristics of cachectin (TNF) and its potential role in therapy]. 194 96

It is currently hypothesized that the mechanisms of cancer cachexia involve the host's production of inflammatory cytokines, which in turn orchestrate a series of complex interrelated steps that ultimately lead to a chronic state of wasting, malnourishment, and death (see Fig. 1). The metabolic changes seen in the tumor-bearing host are similar, but not identical, to those seen in sepsis and inflammation and appear to result from a generalized response of the host to the stimulus of invasion--the tumor. Although there are likely to be several humoral factors, of either host or tumor origin (see Fig. 1), involved in cancer cachexia, recombinant DNA methodology has provided sufficient amounts of only a few cytokines to enable careful investigation of their cachectic potential. TNF/cachectin has been most extensively studied and appears to play a clear role, because administration of low-dose continuous or escalating doses simulates changes associated with cancer cachexia. In addition, these cachectic changes have been blocked by a specific antisera. IL-1, IL-6, and interferon-gamma all have potential as mediators of cancer cachexia and more work is clearly indicated. It is possible that, given our current understanding of the mechanisms of cancer cachexia, it can be theorized that TNF, which causes many of the manifestations of cancer cachexia, and IL-1 are released by macrophages in response to tumor (see Fig. 1). Interferon-gamma appears to potentiate these effects and may also be necessary for the complete syndrome of cancer cachexia. IL-6 probably is released as another mediator, principally mediating the acute phase response seen in cancer cachexia. Other factors are certain to be involved. Further study into the mechanisms and possible treatment of cancer cachexia is needed, because a large proportion of cancer patients who are incurable by current therapies continue to suffer from this lethal wasting diathesis. Furthermore, specific strategies to reverse the cachectic changes associated with cancer will likely improve antitumor treatment.
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PMID:Mechanisms of cancer cachexia. 202 66

We have developed a murine model of wasting by injecting intracerebrally cells which continuously secrete h-cachectin/TNF (CHO-TNF) to: (a) determine the effects of cachectin/TNF produced continuously in the central nervous system (CNS), and (b) compare the metabolic effects of cachectin/TNF-secreting tumor in the brain to the cachexia caused by CHO-TNF tumor in peripheral tissue (IM). Intracerebral CHO-TNF tumors produced increased serum h-cachectin/TNF levels with lethal hypophagia and weight loss (mean survival time of 11 d); these changes were not observed in association with nonsecretory control brain tumors. The metabolic consequences of intracerebral cachectin/TNF production were indistinguishable from acute, lethal starvation: whole-body lipid content was decreased significantly but protein was conserved. Although intramuscular cachectin/TNF-secreting tumors caused similar increases of serum h-cachectin/TNF levels, profound anorexia did not develop; wasting developed after a longer period of tumor burden (50 d) with classical signs of cachexia (i.e., anemia and depletion of both protein and lipid). These studies provide a reproducible animal model of site-specific cytokine production and suggest that, regardless of serum levels, cachectin/TNF produced locally in brain influences both the rate of development of wasting and its net metabolic effects.
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PMID:Metabolic effects of cachectin/tumor necrosis factor are modified by site of production. Cachectin/tumor necrosis factor-secreting tumor in skeletal muscle induces chronic cachexia, while implantation in brain induces predominantly acute anorexia. 225 57

The changes in food intake and biochemistry following Freund's adjuvant (AJ)-induced inflammation in rats were investigated. Injection of AJ into rats resulted in a transient anorexia but a sustained decrease in body weight. Within 14 days, body weight decreased by 12% (P less than 0.05) and adipose tissue (retroperitoneal fat pads) decreased by more than 50%. Biochemical changes seen in association with the AJ-induced wasting included decreased plasma concentrations of triglyceride and cholesterol. Injection of cyclosporin-A (CS) (20 mg/kg) with the AJ decreased the anorexia, prevented the sustained loss of body weight and adipose tissue and reversed the effects on plasma triglyceride and cholesterol concentrations. Insulin concentrations were not significantly affected by the AJ or AJ/CS treatments. Peritoneal macrophages from AJ-treated rats produced 3-fold more tumour necrosis factor-alpha (cachectin) than control rats. This effect was not observed in rats treated with AJ plus CS. The results are consistent with CS preventing the release of cytokines which have anorectic and catabolic actions (IL-1, TNF), although there is also the possibility that CS has effects involving endocrine mechanisms.
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PMID:Prevention of adjuvant-induced cachexia in rats by cyclosporin A. 231 12

A proposed role for the hypothesized toxohormone/s (Vasopressin, Prostaglandin E2 and TNF-Cachectin) in the development and maintenance of cancer cachexia was investigated in rats bearing the Walker 256 carcinosarcoma. Elevated levels of arginine vasopressin and prostaglandin E2 in the plasma and urine were associated with reduced hepatic ketogenesis, fatty acid oxidation and increased fatty acid esterification. The oxidation of branched chain amino acids by the muscle tissue of tumour bearing rats was increased and attributed to the enhanced activity of muscle branched chain keto-acid dehydrogenase. Concerted actions by the triology of factors (AVP, PGE2, Cachectin-TNF) are proposed to instigate a sequence of reactivities that lead to the clinical symptoms of muscle and adipose tissue wasting, together with the negative nitrogen balance characteristic of the cachectic state.
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PMID:Tentative identification of the toxohormones of cancer cachexia: roles of vasopressin, prostaglandin E2 and cachectin-TNF. 235 26

TNF alpha may play a critical role in many physiologic and pathophysiologic responses. It shows a bifunctional regulatory nature of both inhibiting tumor cell proliferation and enhancing growth and differentiation of other cells. TNF alpha acts as a mediator, binding to specific high affinity receptors to elicit biological responses. TNF alpha may be an essential local and systemic mediator in the pathogenesis of cachexia. By inhibiting the activity of lipogenic enzymes, it affects lipid mobilization from adipose tissue and adipocyte differentiation. The ability of TNF alpha to inhibit anabolic processes in adipocytes and preadipocytes is not unique and has been displayed, though to a lesser degree, by other cytokines such as LT, IFN-gamma, and IL-1. In infected animals, the effect of TNF alpha on LPL of inhibiting anabolic processes and enhancing secretion of FFA by adipocytes, may be important in providing additional energy needed by the immune system to combat invasion. However, the relationship between the suppression of the anabolic processes and the cytotoxicity is uncertain and prolonged action may lead to wasting. The evidence suggests that in the adipocyte, TNF alpha is the unique molecule that suppresses LPL through the selective inhibition of mRNA production. As a consequence of the decrease in the enzyme amounts, there is a reduction in TG-uptake and lipid deposition contributing to cachexia. Neutralizing the action of TNF alpha may reverse the cachectic processes and potentially improve the condition. Further research into the induction, synthesis and regulation of TNF alpha production is necessary. Modern molecular biology techniques should serve as useful models in understanding the regulation of TNF alpha functions in response to stimuli. Development of faster and more sensitive detection methods would improve the measurement of the low concentrations of cytokines.
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PMID:The effect of tumor necrosis factor alpha on the activity of lipoprotein lipase in adipose tissue. 268 38

Experiments were performed to determine the effects of hydrazine sulfate (HS), a potential anti-cachexia agent, on tumor necrosis factor activities (cachectin/TNF) in vitro. We present evidence that HS significantly inhibits the lytic activity of TNF on L-929 cells, that HS has no direct effect on TNF itself, and that the minimum amount of time for maximum inhibition of TNF activity to occur after HS treatment is between 1 and 4 h. In addition to HS's effect on the cytolytic activity, we also determined its effect on the antiviral activity of TNF. We found that HS greatly potentiates TNF antiviral activity, while having no significant antiviral activity itself over a range of concentrations, that the potentiation was likely between HS and TNF-induced interferon-B1, and was maximal following 4 and 8 h of treatment with HS. Although the lytic activity of TNF has not been directly correlated with its cachectic activities, these studies provide evidence for an effect of HS on cachectin and its role in the wasting process. Furthermore, a rationale is provided for use of HS in conjunction with TNF for prevention and/or treatment of viral infection.
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PMID:Modulation of tumor necrosis factor activities by a potential anticachexia compound, hydrazine sulfate. 280 26

Cancer cachexia describes a syndrome of progressive weight loss, anorexia, and persistent erosion of host body cell mass in response to a malignant growth. Although often associated with preterminal patients bearing disseminated disease, cachexia may be present in the early stages of tumor growth before any signs or symptoms of malignancy. A decline in food intake relative to energy expenditure (which may be increased, normal, or decreased) is the fundamental physiologic derangement leading to cancer-associated weight loss. In addition, abnormalities of host carbohydrate, protein, and fat metabolism lead to continued mobilization and ineffective repletion of host tissue, despite adequate nutritional support. Mediators of cancer anorexia and associated abnormalities are unknown. Cachectin/TNF or other host-derived cytokines (produced as a defense against malignancy) have been implicated as signal molecules in cachexia, based upon similar metabolic derangements produced by these cytokines in other chronic wasting illnesses. Nutritional support is effective in maintaining body weight of cachectic cancer patients, but ineffective in maintaining lean body mass. Although in one study parenteral nutritional support has improved operative morbidity and mortality in cancer patients, it has not yet improved response to chemotherapy or radiation therapy. Because of metabolic derangements seen in cancer cachexia, effective nutritional treatment regimens will probably require manipulation of host intermediary metabolism in addition to feeding. Insulin therapy or exercise are two such methods which appear to preserve host composition by preferential feeding of the host at the expense of the tumor. Future studies which more clearly define the role of signal molecules in producing cancer cachexia syndrome may lead to new treatment strategies, possibly involving modulation of the effects of such molecules on host metabolism.
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PMID:Cancer cachexia. 329 98


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