Evaluation of in vitro Cytotoxic Effects of Especifico Pessoa Phytotherapic Tincture on Ehrlich Tumor Cells and Mice Spleen Cells

Especifico Pessoa (EP) is traditionally used for the treatment of snakebite envenoming. The traditional use of EP and its properties have been reported. In this study, we evaluated the in vitro cytotoxic effects of EP on Ehrlich tumor and mice spleen cells. Cytotoxicity assay was carried out by using Trypan blue exclusion method. Spleen cell suspension was prepared (n=2) with RPMI medium and tumor cell suspension was prepared from ascitic fluid of Ehrlich tumor-bearing mice (n=1); both the suspensions contained 4 x 106 cells mL-1. Pure EP or EP diluted in RPMI (1:2; 1:4) was used. The results were expressed as percentage of cell viability and demonstrate that EP is toxic to Ehrlich cells at all concentrations (Control: 96.42 ± 3.40; Pure: 1.55 ± 2.91; 1:2: 4.85 ± 5.04; 1:4: 13.39 ± 5.08), but nontoxic to spleen cells in at the lowest dilution (Control: 72.86 ± 13.79; Pure: 13.52 ± 6,36; 1:2: 41.36 ± 13.51; 1:4: 56.59 ± 8.62). Therefore, the results demonstrate that EP has cytotoxic effects, depending on the dose and the cell line evaluated.

Mechanisms of Anthracycline-Enhanced Reactive Oxygen Metabolism in Tumor Cells

In this investigation, we examined the effect of anthracycline antibiotics on oxygen radical metabolism in Ehrlich tumor cells. In tumor microsomes and nuclei, doxorubicin increased superoxide anion production in a dose-dependent fashion that appeared to follow saturation kinetics; the apparent Km and Vmax for superoxide formation by these organelles was 124.9 μM and 22.6 nmol/min/mg, and 103.4 μM and 4.8 nmol/min/mg, respectively. In both tumor microsomes and nuclei, superoxide formation required NADPH as a cofactor, was accompanied by the formation of hydrogen peroxide, and resulted from the transfer of electrons from NADPH to the doxorubicin quinone by NADPH:cytochrome P-450 reductase (NADPH:ferricytochrome oxidoreductase, EC 1.6.2.4). Anthracycline antibiotics also significantly enhanced superoxide anion production by tumor mitochondria with an apparent Km and Vmax for doxorubicin of 123.2 μM and 14.7 nmol/min/mg. However, drug-stimulated superoxide production by mitochondria required NADH and was increased by rotenone, suggesting that the proximal portion of the electron transport chain in tumor cells was responsible for reduction of the doxorubicin quinone at this site. The net rate of drug-related oxygen radical production was also determined for intact Ehrlich tumor cells; in this system, treatment with doxorubicin produced a dose-related increase in cyanide-resistant respiration that was enhanced by changes in intracellular reducing equivalents. Finally, we found that in the presence of iron, treatment with doxorubicin significantly increased the production of formaldehyde from dimethyl sulfoxide, an indication that the hydroxyl radical could be produced by intact tumor cells following anthracycline exposure. These experiments suggest that the anthracycline antibiotics are capable of significantly enhancing oxygen radical metabolism in Ehrlich tumor cells at multiple intracellular sites by reactions that could contribute to the cytotoxicity of this class of drugs.

Ultrapathological evaluation of the anticancer effect of blackseed (Nigella sativa) and garlic (Allium sativum) in mice

In this experimental work, 120 virgin female mice (body weight 40±10 gm) were divided into 6 equal groups. Mice in Group 1 served as a control. Mice in Groups 2 and 3 were fed on a basal diet provided with 100 mg/kg b.wt from each of blackseed (<em>Nigella sativa</em>) and garlic (<em>Allium sativum</em>), respectively, for one month. Mice in Group 4 were inoculated subcutanously (S/C) with Ehrlich tumor cells after one month from the start of the experiment. Mice in Groups 5 and 6 were treated similarly to those in Groups 3 and 4, respectively, for one month and then immediately inoculated S/C with Ehrlich tumor cells (ETC, 0.1 mL/mouse). Blood samples were taken from mice of Groups 1, 2 and 3 at one month of experiment and tissue specimens were collected from mice in all groups two weeks after inoculation of Ehrlich tumor cells. Histopathologically, Groups 2 and 3 showed proliferation of mononuclear phagocytic system and mild degeneration of internal organs. In Group 4, histopathology revealed neoplastic mass with signs of malignancy, ultrastructurely exhibited pleomorphism, degenerated organelles with activated euo- and heterochromatin and cavitations of the cytoplasm. Groups 5 and 6 revealed much smaller neoplastic growth with necrosis and hemorrhage. The necrotic neoplastic cells replaced by empty cavities with congested blood vessels, the others showed pyknotic or karryolytic nuclei. In Groups 5 and 6, the electron microsopic appearance of the neoplastic growth exhibited degenerated and swollen cells with multiple cavitations. Most of the cytoplasmic organelles were degenerated with activation of lysozymes. It could be concluded that, both garlic and black seed minimize the histopathological and electron microscopic alterations of ETC in mice.

The Ehrlich Tumor Induces Pain-Like Behavior in Mice: A Novel Model of Cancer Pain for Pathophysiological Studies and Pharmacological Screening

The Ehrlich tumor is a mammary adenocarcinoma of mice that can be developed in solid and ascitic forms depending on its administration in tissues or cavities, respectively. The present study investigates whether the subcutaneous plantar administration of the Ehrlich tumor cells induces pain-like behavior and initial pharmacological susceptibility characteristics. The Ehrlich tumor cells (1 × 104–107cells) induced dose-dependent mechanical hyperalgesia (electronic version of the von Frey filaments), paw edema/tumor growth (caliper), and flinches compared with the saline group between days 2 and 12. There was no difference between doses of cells regarding thermal hyperalgesia in the hot-plate test. Indomethacin (a cyclooxygenase inhibitor) and amitriptyline hydrochloride (a tricyclic antidepressant) treatments did not affect flinches or thermal and mechanical hyperalgesia. On the other hand, morphine (an opioid) inhibited the flinch behavior and the thermal and mechanical hyperalgesia. These effects of morphine on pain-like behavior were prevented by naloxone (an opioid receptor antagonist) treatment. None of the treatments affected paw edema/tumor growth. The results showed that, in addition to tumor growth, administration of the Ehrlich tumor cells may represent a novel model for the study of cancer pain, specially the pain that is susceptible to treatment with opioids, but not to cyclooxygenase inhibitor or to tricyclic antidepressant.

Swim training suppresses tumor growth in mice

The present study was designed to determine the effects of physical training on the development of cancer induced by the injection of Ehrlich tumor cells in mice. Male Swiss mice were subjected to a swim training protocol (5 days/wk for 6 wk, 1 h at 50% of maximal capacity-trained groups) or remained sedentary in their cages (sedentary groups). The inoculation of Ehrlich tumor cells was performed at the end of the fourth week, and animals were killed after 6 wk of training. Heart and solid tumor weights were recorded, and tumor volumes were calculated. Portions of the tumors were used for the evaluation of macrophages and neutrophil accumulation or fixed in neutral 10% buffered formalin for histological analysis. The tumor volume and weight were, respectively, ∼270% and 280% greater in sedentary mice than in trained mice. Macrophage infiltration in the tumor tissue was significantly lower in trained mice (0.65 ± 0.16 vs. 1.78 ± 0.43 macrophages × 103 in the sedentary group). Moreover, neutrophil accumulation in tumors was slightly reduced after exercise training, and the amount of tumor cells was reduced in trained mice. Exercise capacity was substantially increased in trained mice, as determined by a 440% increase in the exercise time at 50% of maximal capacity. In summary, swim training retarded the development of Ehrlich tumors in mice, accompanied by a reduction in macrophage infiltration and neutrophil accumulation. These findings provide conceptual support for clinical observations that controlled physical activities may be a therapeutically important approach to preventing cancer progression and may improve the outcome of cancer treatment.

AFM studies of DNA structures extracted from adriamycin treated and non-treated Erlich tumor cells

Atomic force microscopy (AFM), a unique tool to investigate drug treatment of cancer cells, was used to analyze the anti-neoplastic activity of adriamycin by comparing DNA structures of non-treated and adriamycin-treated Ehrlich tumor cells. The non-treated cells exhibited a highly branched intact chromatin structure, related to the intensive DNA replication in cancer cells. Images from adriamycin-treated tumor cells showed that the DNA chains were broken and the chromatin structure had been destroyed. Possible explanations for these effects of adriamycin are considered: breakage of hydrogen bonding, oxidation and intercalation effects, as well as the poisoning of topoisomerase enzyme. DNA fractal and multifractal analyses performed in order to evaluate the degree of bond scission, showed that the treated DNA had become more fractal compared to non-treated DNA.