Pioglitazone treatment increases survival and prevents body weight loss in tumor-bearing animals: possible anti-cachectic effect.

Cachexia is a multifactorial syndrome characterized by profound involuntary weight loss, fat depletion, skeletal muscle wasting, and asthenia; all symptoms are not entirely attributable to inadequate nutritional intake. Adipose tissue and skeletal muscle loss during cancer cachexia development has been described systematically. The former was proposed to precede and be more rapid than the latter, which presents a means for the early detection of cachexia in cancer patients. Recently, pioglitazone (PGZ) was proposed to exhibit anti-cancer properties, including a reduction in insulin resistance and adipose tissue loss; nevertheless, few studies have evaluated its effect on survival. For greater insight into a potential anti-cachectic effect due to PGZ, 8-week-old male Wistar rats were subcutaneously inoculated with 1 mL (2×107) of Walker 256 tumor cells. The animals were randomly assigned to two experimental groups: TC (tumor + saline-control) and TP5 (tumor + PGZ/5 mg). Body weight, food ingestion and tumor growth were measured at baseline and after removal of tumor on days 7, 14 and 26. Samples from different visceral adipose tissue (AT) depots were collected on days 7 and 14 and stored at -80o C (5 to 7 animals per day/group). The PGZ treatment showed an increase in the survival average of 27.3% (P< 0.01) when compared to TC. It was also associated with enhanced body mass preservation (40.7 and 56.3%, p< 0.01) on day 14 and 26 compared with the TC group. The treatment also reduced the final tumor mass (53.4%, p<0.05) and anorexia compared with the TC group during late-stage cachexia. The retroperitoneal AT (RPAT) mass was preserved on day 7 compared with the TC group during the same experimental period. Such effect also demonstrates inverse relationship with tumor growth, on day 14. Gene expression of PPAR-γ, adiponectin, LPL and C/EBP-α from cachectic rats was upregulated after PGZ. Glucose uptake from adipocyte cells (RPAT) was entirely re-established due to PGZ treatment. Taken together, the results demonstrate beneficial effects of PGZ treatment at both the early and final stages of cachexia.

Asparagus polysaccharide and gum with hepatic artery embolization induces tumor growth and inhibits angiogenesis in an orthotopic hepatocellular carcinoma model.

Liver cancer is one of leading digestive malignancies with high morbidity and mortality. There is an urgent need for the development of novel therapies for this deadly disease. It has been proven that asparagus polysaccharide, one of the most active derivates from the traditional medicine asparagus, possesses notable antitumor properties. However, little is known about the efficacy of asparagus polysaccharide as an adjuvant for liver cancer chemotherapy. Herein, we reported that asparagus polysaccharide and its embolic agent form, asparagus gum, significantly inhibited liver tumor growth with transcatheter arterial chemoembolization (TACE) therapy in an orthotopic hepatocellular carcinoma (HCC) tumor model, while significantly inhibiting angiogenesis and promoting tumor cell apoptosis. Moreover, asparagine gelatinous possessed immunomodulatory functions and showed little toxicity to the host. These results highlight the chemotherapeutic potential of asparagus polysaccharide and warrant a future focus on development as novel chemotherapeutic agent for liver cancer TACE therapy.

Naringin inhibits tumor growth and reduces interleukin-6 and tumor necrosis factor α levels in rats with Walker 256 carcinosarcoma.

The flavonoid naringin is a polyphenolic compound that naturally occurs in citrus. Patients with cancer generally present features of malnutrition and cachexia. Levels of the proinflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) are raised in patients with cancer. This study was designed to analyze the in vivo effect of naringin in the therapeutic treatment of rats bearing Walker 256 carcinosarcoma (W256). Rats were treated intraperitoneally with different doses of naringin (10, 25 and 35 mg/kg), for 50 days. At 25 mg/kg, naringin inhibited tumor growth by ~75%. With this treatment, TNF-α and IL-6 levels decreased (p<0.05) in comparison with the control. In addition, two rats presented complete tumor regression. Inhibition of tumor growth, survival increase and the reduction of TNF-α and IL-6 levels in rats bearing W256 treated with naringin strongly suggest that this compound has potential as an anticarcinogenic drug.

Effect of fish oil supplementation for two generations on changes of lymphocyte function induced by Walker 256 cancer cachexia in rats.

Fish oil supplementation has been shown to improve the cachectic state of tumor-bearing animals and humans. Our previous study showed that fish oil supplementation (1 g per kg body weight per day) for 2 generations had anticancer and anticachetic effects in Walker 256 tumor-bearing rats as demonstrated by reduced tumor growth and body weight loss and increased food intake and survival. In this study, the effect of fish oil supplementation for 2 generations on membrane integrity, proliferation capacity, and CD4/CD8 ratio of lymphocytes isolated from mesenteric lymph nodes, spleen, and thymus of Walker 256 tumor-bearing animals was investigated. We also determined fish oil effect on plasma concentration and ex vivo production of cytokines [tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), IL-6, and IL-10]. Lymphocytes from thymus of tumor-bearing rats presented lower viability, but this change was abolished by fish oil supplementation. Tumor growth increased proliferation of lymphocytes from all lymphoid organs, and fish oil supplementation abolished this effect. Ex vivo production of TNF-alpha and IL-6 was reduced in supplemented animals, but IL-4 and IL-10 secretion was stimulated in both nontumor and tumor-bearing rats. IL-10 and IFN-gamma plasma levels was also decreased in supplemented animals. These results suggest that the anticachetic effects of fish oil supplementation for a long period of time (2 generations) in Walker 256 tumor-bearing rats may be associated to a decrease in lymphocyte function as demonstrated by reduced viability, proliferation capacity, and cytokine production.

Beta-hydoxy-beta-methylbutyrate supplementation affects Walker 256 tumor-bearing rats in a time-dependent manner.

BACKGROUND & AIMS: Cancer cachexia affects intermediary metabolism with intense and general catabolism. Walker 256 tumor is a model injected either subcutaneously (Sc) or intraperitoneally (Ip), with different metabolic features. Beta-hydroxy beta-methylbutyrate (HMbeta) is a leucine metabolite with anti-catabolic properties, the aim of this study being to investigate its effects on metabolic parameters in both tumor models. METHODS: Controls (subcutaneous control group (ScC) and intraperitoneal control group (IpC)) and supplemented animals (subcutaneous supplemented group (ScS) and intraperitoneal supplemented group (IpS)) showed these results. RESULTS: Protein Sc values were (47.8%) lower than Ip groups. Sc group fat content was (65.16%) higher than Ip groups. Liver glycogen value for Sc groups was (38.4%) higher than Ip groups. Muscle glycogen value for Sc groups were (2.75 times) higher than Ip groups. Corticosterone and insulin values were lower (44.53%) and higher (45.94%), respectively, in Sc when compared with Ip groups. Glucose and lactate values for ScS were the lowest (61.7% and 41.53%) compared to other groups. ScC glutamine value was the highest (40.8%) of all groups. Glutamate Sc values were (42.65%) lower than Ip groups. Sc groups showed greater survival time compared with Ip groups. ScS group showed 100% increase in survival time when compared with ScC. CONCLUSIONS: HMbeta supplementation can increase survival time and promotes metabolic changes in cancer-bearing animals, but it seems to work in a time-dependent manner.

Enhanced antitumor efficacy on hepatoma-bearing rats with adriamycin-loaded nanoparticles administered into hepatic artery.

AIM: To investigate the antitumor activity of adriamycin (ADR) encapsulated in nanoparticles (NADR) and injected into the hepatic artery of hepatoma-bearing rats. METHODS: NADR was prepared by the interfacial polymerization method. Walker-256 carcinosarcomas were surgically implanted into the left liver lobes of 60 male Wistar rats, which were divided into 4 groups at random (15 rats per group). On the 7th day after implantation, normal saline (NS), free ADR (FADR), NADR, or ADR mixed with unloaded nanoparticles (ADR+NP) was respectively injected via the hepatic artery (i.a.) of rats in different groups. The dose of ADR in each formulation was 2.0 mg/kg body weight and the concentration was 1.0 mg/mL. Survival time, tumor enlargement ratio, and tumor necrosis degree were compared between each group. RESULTS: Compared with the rats that received NS i.a., the rats that received FADR or ADR+NP acquired apparent inhibition on tumor growth, as well as prolonged their life span. Further significant anticancer efficacy was observed in rats that received i.a. administration of NADR. Statistics indicated that NADR brought on a more significant tumor inhibition and more extensive tumor necrosis, as compared to FADR or ADR+NP. The mean tumor enlargement ratio on the 7th day after NADR i.a. was 1.106. The mean tumor-bearing survival time was 39.50 days. Prolonged life span ratio was 109.22% as compared with rats that accepted NS. CONCLUSION: Therapeutic effect of ADR on liver malignancy can be significantly enhanced by its nanopaticle formulation and administration via hepatic artery.

Cancer cachexia and tumor growth reduction in Walker 256 tumor-bearing rats supplemented with N-3 polyunsaturated fatty acids for one generation.

In this study we investigated the effect of lifelong supplementation of the diet with coconut oil (CO, rich in saturated fatty acids) or fish oil (FO, rich in n-3 polyunsaturated fatty acids, PUFAs) on tumor growth, animal survival, and metabolic indicators of cachexia in adult rats. Female Wistar rats were supplemented with CO or FO prior to mating and then throughout pregnancy and gestation, and then the male offspring were supplemented from weaning until 90 days of age. Then they were inoculated subcutaneously with Walker 256 tumor cells. Tumor weight at 14 days in control rats (those fed standard chow) was approximately 20 g. These animals displayed cancer cachexia, which was characterized by loss of weight, hypoglycemia, hyperlacticidemia, hypertriacylglycerolemia, and depletion of glycogen stores. Supplementation of the diet with CO did not change these parameters, except that there was a smaller decrease in serum triacylglycerol concentration. Supplementation of the diet with FO significantly decreased tumor growth (by approximately 60%), increased survival (50% at 30 days postinoculation vs. 30% in the controls and 13.5% in the CO group), and prevented the fall in body weight. Furthermore, FO supplementation partly abolished the fall in serum glucose, totally prevented the elevation in serum lactate concentrations, partly prevented the hypertriacylgylcerolemia, and preserved tissue glycogen stores. Lifelong consumption of FO, rich in n-3 PUFAs, protects against tumor growth and cancer cachexia and improves survival.

Effect of a moderate intensity exercise training protocol on the metabolism of macrophages and lymphocytes of tumour-bearing rats.

It is commonly accepted that moderate intensity exercise is beneficial to the immune system. We tested the influence of a moderate intensity training protocol (8 weeks) upon immune system function in Wistar tumour-bearing (TB) rats. The metabolism of glucose and glutamine in lymphocytes and macrophages was assessed, together with some functional parameters (hydrogen peroxide production and lymphocyte proliferative response). These substrates were chosen since they represent the most important energetic and synthetic metabolites for these cellular types. The training protocol caused a decrease of 17.4 per cent in the production of H(2)O(2) by macrophages, as well as a decrease in glucose consumption (25 per cent) and lactate production (47.1 per cent), and an increase in the production of labelled CO(2) from the oxidation of [U-(14)C]-glucose, in TB rats. The training protocol was also able to induce changes in the maximal activity of some key enzymes in the metabolism of glucose and glutamine, a reduction of hexokinase (68.8 per cent) activity and an increase in the activity of citrate synthase (10.1 per cent) in TB rats. The training protocol increased the proliferative response of lymphocytes cultivated in the absence of mitogens (75 per cent), of those cultivated in the presence of ConA (38.2 per cent) and in the presence of LPS (45.0 per cent). These cells also showed an increase in the maximal activity of some key enzymes of the glycolytic and glutaminolytic pathways. Our data demonstrated that the training protocol was able to induce an increase in aerobic utilisation of both substrates in lymphocytes and macrophages. The training protocol was also able to prevent several changes in glucose and glutamine metabolism that are normally present in sedentary TB rats. These changes in immune cell metabolism induced by the training protocol were able to increase TB rat survival.

Ultrastructural changes induced in Walker carcinosarcoma by treatment with dihematoporphyrin ester and light in animals with diabetes mellitus.

The purpose of this study was to evaluate by electron microscopy the tumoral fine structure changes induced by photodynamic therapy (PDT) in diabetic animals. Walker -256 carcinosarcoma harvested from animals with/without diabetes mellitus exposed to PDT (Photofrin II/5 mg/kg and 24 hrs later He-Ne laser irradiation/632.8 nm; 10 mW) and examined by electron microscopy showed different degrees of lesions in the nucleus and cytoplasmic fine structure. The ultrastructural changes induced by PDT in animals with diabetes mellitus bearing carcinosarcoma are characterized by: lysis of chromatin situated on the central zone of nucleus; swelling and vacuolization of mitochondria; formation of phagosome--like structures; myelin figures; degenerescence and disappearance of cytoplasmic organelles. Summing up, the data presented in this work demonstrate that the exposure to three doses of PDT produces changes in tumoral fine structure, increases survival rate and reduces incidence of carcinosarcoma in rats with diabetes mellitus.

[Action of 3,5,3'-triiodothyronine (T3) on Walker's 256 carcinosarcoma development]. / Ação da 3,5,3'-triiodotironina (T3) sobre a evolução do carcinossarcoma 256 de Walker.

In order to verify the effects of triiodothyronine (T3) administration in animals bearing Walker tumor, the authors have carried out an experimental study utilizing Wistar rats inoculated with both ascitic and solid Walker tumor, and Balb/c isogenic mice for the study of spreading of macrophages. The animals were treated with T3 20 micrograms/100 g of body weight and the data were analysed by Chi-square and Mann-Whitney tests. The authors conclude that T3 increases significantly the survival of rats bearing Walker tumor, and the spreading of macrophages when inoculated into the peritoneal cavity of mice. The hormone does not alter the weight of tumor mass. These results could be explained by the macrophageal activation and by the synthesis of the tumor necrosis factor.

A sobrevida de ratos com tumor de Walker submetidos previamente à imunogenicidade das células tumorais / Survival in rats with Walker's tumor submitted previously to the tumoral cells immunogenicity

A inoculaçao de 37.10 5 células do tumor de Walker, por via intramuscular, na coxa do rato confirmou uma evoluçao rápida do mesmo, ao exibir um crescimento expansivo da massa tumoral no local do inóculo, culminando com a morte do animal. Todavia, quando da inoculaçao em ratos expostos previamente à "imunogenicidade destas células", observou-se uma evoluçao mais lenta e uma maior sobrevida, sugerindo modulaçao na imunidade destes animais. O contato prévio com as células tumorais ou ainda a fraca imunogenicidae destas células, provavelmente, possa ter sido suficiente e responsável pelo retardo no desenvolvimento do tumor e pela maior sobrevida dos animais

[The influence on tumor growth and the function of the thiol-dependent systems of the liver of excess cooking fat and vitamin E in the diet. The effects of carminomycin]. / Vliianie na opukholevyi rost i sostoianie tiolzavisimykh sistem pecheni izbytka kulinarnogo zhira i vitamina E v ratsione. Effekty karminomitsina.

A study was made of the influence of excessive culinary fat in the diet containing 30% of trans-isomers and tocopherol on tumor growth, parameters of antitumor and toxic action of carminomycin, and the state of thiol-dependent defensive systems of the liver. The data obtained have evidenced a negative influence of the experimental ration on the survival of the tumor-carriers and on the condition of the normal animals. Activation of the glutathion S-transferase system attended by the exhaustion of the thiol pool in the liver was recorded. Carminomycin toxic action was not modified by the experimental diet.

[The effect of ferromagnet particles on the growth of Walker carcinosarcoma 256 in Wistar rats]. / Vliianie ferromagnitnykh chastits na rost kartsinosarkomy Uoker 256 u krys Wistar.

The intravenous injection of ferromagnetic particles (FMP) was studied for its effect on the growth of Walker 256 carcinosarcoma in Wistar rats. The injection of FMP in a dose of 750 mg/kg increased the organism resistance to the tumour development against a background of phagocytic reaction activation in neutrophils. The injection of FMP in a dose up to 2 g/kg inhibited the phagocytic reactions of neutrophils and accelerated the tumour growth. The data obtained evidence that depending on the FMP dose the total reactivity of the organism may either increase or decrease, thus changing, respectively, its resistance to the development of the tumour process.

[The effect of whole-body and local irradiation, modified by hyperglycemia, on the metastasis of Walker carcinosarcoma 256 in rats]. / Vliianie obshchego i lokal'nogo oblucheniia, modifitsirovannogo giperglikemiei, na metastazirovanie kartsinosarkomy Uoker 256 u krys.

It has been shown that the local radiation therapy, and also radiation therapy modified by the short-term hyperglycemia really increase the life-span of rats with Walker 256 carcinosarcoma. At the same time the metastatic process also increases, especially after the modified radiation therapy. The total irradiation of experimental animals in a dose of 50 sGy before the modified radiation therapy considerably decreases the frequency of metastatic process. A conclusion is drawn that the total irradiation has a prophylactic influence on metastases under conditions of modified radiation therapy.

Tumor growth promoting activity of an immunosuppressive substance and its modulation by protein-bound polysaccharide PSK.

The role of an immunosuppressive substance (IS), which is increased in the serum of tumor-bearing animals, was examined in rats. IS isolated from cancerous ascites fluid of rats was administered to Walker 256 tumor-bearing rats to examine changes in the serum level of IS, tumor growth and survival rate. PSK, an immunomodulator, was also administered. Serum IS increased with tumor growth. The administration of IS to tumor-transplanted rats caused the tumor to grow and shortened the animals' survival time. The administration of PSK, however, inhibited the increase in serum level of IS, resulting in the suppression of tumor growth and a prolongation of survival time. The findings suggested that IS is a useful parameter for predicting not only tumor growth but also the therapeutic effect of immunomodulators such as PSK.

Effect of a protein bound polysaccharide (PS-K) on tumor development and infections in splenectomized rats and mice.

Daily oral administration of PS-K, an immunomodulating agent, was found to improve survival rate in tumor bearing mice and rats and to decrease susceptibility to infection in mice. Surprisingly, splenectomized tumor bearing rats and mice responded better to PS-K treatment as measured by survival rate, tumor size and immunosuppressive properties of serum. The mechanism of PS-K antitumor activity in both experimental systems might be due to the alteration of splenic immune suppressive mechanisms during tumor growth in the host. On the other hand, host resistance to acute infection was found to be less dependent upon the presence or absence of spleen suggesting a different mechanism of PS-K activity in acute infectious disease.

[Enhancement of the antitumor effect of cyclophosphane in an experiment]. / Povyshenie protivoopukholevogo éffekta tsiklofosfana v éksperimente.

A significant antitumor effect of acetylcellulose microsphere-encapsulated cyclophosphamide was observed in the course of the studies carried out in 105 male Wistar rats bearing Walker's carcinosarcoma and PC-1 carcinoma. The effect is due to a high tissue level of the drug maintained for a long time as the drug uniformly passes through the porous microsphere wall. Local (intratumoral) treatment with cyclophosphamide is more effective than standard methods. The inhibitory effect of microsphere-enclosed cyclophosphamide on neoplastic growth is potentiated by tumor ischemia.

Studies of amygdalin (laetrile) toxicity in rodents.

Amygdalin (laetrile), given to Fischer 344 rats in doses of 250, 500, and 750 mg/kg intraperitoneally daily for five days, caused mortalities of 30.8% 44.1%, and 56.8%, respectively. The mode of death and the elevated serum cyanide levels in the dying animals strongly suggested cyanide poisoning as the cause of death. These findings seriously question the use of amygdalin in clinical medicine under any circumstances.