Cristina de Oliveira Massoco

Effects of physical and psychological stressors on behavior, macrophage activity, and Ehrlich tumor growth

The present study analyzed the effects of physical and psychological stressors on behavior, immune function, and serum corticosterone in mice. Adult mice were submitted once daily, for 6 days to one of the following conditions: escapable (ES) or inescapable (IS) footshocks (0.2 mA) signaled by a tone cue or to a psychological stressor (PS) generated through the use of a communication box; in this box, mice received no footshock but were exposed to responses delivered by IS mice. Results showed that IS and PS: (1). decreased locomotor activity observed in an open-field; (2). decreased number of entries into the open arms and decreased time spent in the exploration of the open arms of the plus-maze; (3). decreased macrophage spreading and phagocytosis; (4). increased macrophage H(2)O(2) release; and (5). increased growth of the ascitic form of Ehrlich tumor. Behavioral and/or immunological changes were not observed after ES; this absence of effects, however, might not be attributed solely to footshock controllability since mice of groups ES and IS differed with respect to the psychological setting used and the amount of shock they received. An increase of serum corticosterone concentrations was also observed in the stressed mice of all groups; this increment was higher in animals of group IS. These data provide evidence that inescapable footshock and psychological stressors alter, at the same time and in mice, stress levels, macrophage activity, and Ehrlich tumor growth. They also show that ES and PS induced similarly elevated serum corticosterone concentrations, but significantly differ in the immunological and behavioral outcomes they produced in mice. These findings suggest that another factor besides HPA axis activation might be responsible for behavioral and immunological consequences of IS and PS in mice. It is proposed that the final neural link between behavioral and immunological changes observed after physical and psychological stressors might involve catecholaminergic systems within the central nervous system and/or sympathetic autonomic nerve fibers and also opioid peptides.

Effects of prenatal stress on stress-induced changes in behavior and macrophage activity of mice

The present study analyzed the effects of maternal stress on behavior and macrophage activity of mice. Pregnant mice received a daily footshock (0.2 mA) from gestational days 15 (GD15) to 19. Experiments were performed on male offspring, challenged or not with another footshock (0.2 mA) on postnatal day 30 (PND30) or 60. The following results were obtained for maternal stress: (1) increment in locomotor activity of juvenile but not of adult mice observed in both open-field and plus-maze; (2) increment in rearing frequency of juvenile but not of adult mice observed in the open-field; (3) decrement in macrophage spreading of adult but not of juvenile mice; (4) abolishment of postnatal footshock effects in both macrophage spreading on PND30 and macrophage nitric oxide (NO) production on PND60; (5) reversion of postnatal footshock effects on H(2)O(2) spontaneous and PMA-induced release by macrophage on PND30; (6) modification of postnatal stress effects on macrophage phagocytosis on PND60. These changes were unrelated to differences in gestational parameters and did not reflect altered maternal-pup interactions or nutritional factors. The observed data provide experimental evidence that maternal stress alters behavior, and macrophage activity at the same time and in the same litter. These data were discussed in the light of possible neuroimmune interactions that involve catecholaminergic pathways.

Effects of maternal stress on anxiety levels, macrophage activity, and Ehrlich tumor growth

The present study analyzed the effects of maternal stress on behavior and immune function of mice. Pregnant mice received a daily footshock (0.4 mA) from gestational day 15 (GD 15) to GD 19. Experiments were performed on male offspring aged 2 months. The following results were obtained for offspring from dams stressed during pregnancy: (1) decreased locomotor activity observed in the open-field central zone; (2) decreased number of entries into the open arms of the plus-maze and decreased time spent in the exploration of these arms; (3) decreased macrophage spreading and phagocytosis, but no changes in macrophage NO(2)(-) production; (4) increased growth of both the ascitic and solid forms of Ehrlich tumor. These changes were unrelated to differences in gestational parameters and did not reflect altered maternal-pup interactions or nutritional factors. The observed data provide experimental evidence that maternal stress alters stress/anxiety levels, macrophage activity and Ehrlich tumor growth at the same time and in the same litter. The data were discussed in the light of possible neuroendocrine-immune system interactions.

Diazepam effects on peritoneal macrophage activity and corticosterone serum levels in balb/c mice

In the present experiment we investigate the effects of diazepam on macrophage activity and serum corticosterone levels in mice. Adult mice were treated with diazepam (1.5 mg/kg/day - group E) or with control solution (group C1) for 7 days; some animals were only handled, receiving no treatment (group C2). Oral onco-BCG was used for peritoneal macrophage activation. Diazepam treatment: 1-decreased macrophage spreading and phagocytosis; 2-decreased the concentrations of H2O2 spontaneously but not phorbol myristate-acetate-induced release. In relation to mice of group C1, diazepam treatment increased the serum levels of corticosterone. No differences were detected between data of groups C1 and C2 both for macrophage activity and serum corticosterone levels. The present data were explained on the basis of a synergistically action for diazepam through peripheral type binding sites (PBR) present in both adrenals and macrophages, stimulating adrenal glucocorticoid production and altering the macrophage cytokine network.

Stress-induced increment on total bronchoalveolar cell count in OVA-sensitized rats

The influence of stress on total leukocyte count from bronchoalveolar lavage (BAL) was investigated in rats sensitized and challenged with ovalbumin (OVA). The animals were injected intraperitoneally with a suspension of OVA plus aluminum hydroxide in 0.9% NaCl (Day 0) and boosted at Day 7 with an identical OVA solution, administered subcutaneously. From the first to the 13th day after sensitization, rats were placed individually in a shuttle box where they received 50 escapable footshocks per day, always preceded by a sound signal (S); the responses that occurred during both S and shocks canceled the stressful stimulation. On Day 14, animals were submitted to a single session of 50 inescapable footshocks, preceded by the same S; immediately after, the animals were submitted to a 1% OVA-inhalation challenge. Results showed high levels of stress in the shocked animals as detected through both ultrasonic vocalizations (UVs) and social interaction test in an open field. Total leukocyte count in BAL from stressed animals (24 h post-OVA challenge) revealed a significant increase in the number of inflammatory cells in comparison to that measured in sensitized, nonstressed challenged rats. These data demonstrate that stress plays a relevant and important role on total bronchoalveolar cell count in OVA-sensitized rats.

The involvement of miR-100 in bladder urothelial carcinogenesis changing the expression levels of mRNA and proteins of genes related to cell proliferation, survival, apoptosis and chromosomal stability

IntroductionMicroRNAs (miRNA) are small non-coding RNAs that play an important role in the control of gene expression by inhibiting protein translation or promoting messenger RNA degradation. Today, miRNAs have been shown to be involved in various physiological and pathological cellular processes, including cancer, where they can act as oncogenes or tumor suppressor genes. Recently, lowered expression of miR-100, resulting in upregulation of FGFR3, has been correlated with low-grade, non-invasive bladder urothelial cancer, as an alternative oncogenesis pathway to the typical FGFR3 gene mutation. Our aim is to analyze the role of miR-100 in bladder cancer cell lines in controlling the expression of some of its possible target genes, including FGFR3 and its relationship with proliferation, apoptosis and DNA ploidy.MethodsThe bladder cancer cell lines RT4 and T24 were transfected with pre-miR 100, anti-miR 100 and their respective controls using a lipid-based formulation. After transfection mRNA and protein levels of its supposed target genes THAP2, BAZ2A, mTOR, SMARCA5 and FGFR3 were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation, apoptosis and DNA ploidy were analyzed by flow cytometry. For statistical analysis, a t-test was applied, p < 0.05 was considered significant.ResultsAfter miR-100 transfection, there was a significant reduction in the mRNA of mTOR (p = 0.006), SMARCA5 (p = 0.007) and BAZ2A (p = 0.029) in RT4, mTOR (p = 0.023) and SMARCA5 (p = 0.015) in T24. There was a reduction in the expression of all proteins, variable from 22.5% to 57.1% in both cell lines. In T24 miR-100 promoted an increase in cell proliferation and anti-miR 100 promoted apoptosis characterizing miR-100 as an oncomiR in this cell line representative of a high-grade urothelial carcinoma.ConclusionmiR-100 transfection reduces expression of BAZ2A, mTOR and SMARCA5 mRNA and protein in BC cell lines. miR-100 would be classified as an oncomiR in T24 cells representative of high grade urothelial carcinoma promoting increase in cell proliferation and reduction in apoptosis. The knowledge of miRNA role in tumors will allow their use as tumor markers and targets for new therapies.

Comparative Aspects of Canine Melanoma

Melanomas are malignant neoplasms originating from melanocytes. They occur in most animal species, but the dog is considered the best animal model for the disease. Melanomas in dogs are most frequently found in the buccal cavity, but the skin, eyes, and digits are other common locations for these neoplasms. The aim of this review is to report etiological, epidemiological, pathological, and molecular aspects of melanomas in dogs. Furthermore, the particular biological behaviors of these tumors in the different body locations are shown. Insights into the therapeutic approaches are described. Surgery, chemotherapy, radiotherapy, immunotherapy, and the outcomes after these treatments are presented. New therapeutic perspectives are also depicted. All efforts are geared toward better characterization and control of malignant melanomas in dogs, for the benefit of these companion animals, and also in an attempt to benefit the treatment of human melanomas.

Nepeta cataria L. var. citriodora (Becker) increases penile erection in rats.

ETHNOPHARMACOLOGICAL RELEVANCE Nepeta cataria (NC), catnip, induces pleasure in cats and humans. AIM OF THE STUDY Because sexual behavior is involved in pleasure, the effect of NC on sexual behavior and penile erection was evaluated in male rats that were acutely fed chow enriched with 10% NC leaves. Further, yawning was monitored because we previously demonstrated that NC modifies dopaminergic-related behaviors and that sexual behavior is closely linked with the dopaminergic system. The general activity and the motor coordination were examined to investigate the possible motor and emotional interferences of the sexual performance. MATERIAL AND METHODS Male rats of the NC group received for a 4h period the chow enriched with 10% NC leaves while the control groups received regular chow. Fifteen min after the end of the 4h period of NC feeding the sexual behavior, apomorphine-induced penile erection and motor coordination were observed; the general activity in the open field was assessed 0, 15, 30 and 60 min after treatment. RESULTS NC treatment increased male rats penile erection. A slightly facilitation on male rat sexual behavior and a decreased in general activity of NC treated rats were observed. No effects on motor coordination and yawning episodes were detected by the NC treatment. CONCLUSIONS It was suggested that NC increases penile erection and slightly improves male rat sexual behavior by an action on dopaminergic systems.

Autologous processed plasma: cytokine profile and effects upon injection into healthy equine joints.

This experimental controlled study was performed to evaluate the composition of autologous processed plasma (APP), and the effects of APP intra-articular injection into healthy equine metacarpophalangeal joints. The effects on joints were analysed with a short-phase protocol and a prolonged-phase protocol using saline-injected joints as controls. For the short protocol, horses received one intra-articular APP injection. Synovial fluid samples were collected prior to the injection and 3, 6, 24, 48, and 16 h after treatment. For the prolonged protocol, the joints received three weekly injections of APP, and samples were collected at 0, 7, 14, 21, and 28 days before APP administration. IL1-ra level was found to be increased in APP compared to plasma. Upon intra-articular administration of APP, transient (up to 24 h) increases in white blood cell (WBC) counts along with elevated protein and prostaglandin E2 (PGE2) concentrations were observed in the treated joints. Over the 28-day observation period, APP did not elicit changes relative to baseline levels, but WBC counts, PGE2 and chondroitin sulphate concentrations were lower than those found in the control. In conclusion, APP intra-articular injection induced a mild and transitory inflammatory response but no inflammation reaction was observed over a longer period of treatment and observation.

Lung hyperinflation stimulates the release of inflammatory mediators in spontaneously breathing subjects

Lung hyperinflation up to vital capacity is used to re-expand collapsed lung areas and to improve gas exchange during general anesthesia. However, it may induce inflammation in normal lungs. The objective of this study was to evaluate the effects of a lung hyperinflation maneuver (LHM) on plasma cytokine release in 10 healthy subjects (age: 26.1 +/- 1.2 years, BMI: 23.8 +/- 3.6 kg/m(2)). LHM was performed applying continuous positive airway pressure (CPAP) with a face mask, increased by 3-cmH(2)O steps up to 20 cmH(2)O every 5 breaths. At CPAP 20 cmH(2)O, an inspiratory pressure of 20 cmH(2)O above CPAP was applied, reaching an airway pressure of 40 cmH(2)O for 10 breaths. CPAP was then decreased stepwise. Blood samples were collected before and 2 and 12 h after LHM. TNF-alpha, IL-1beta, IL-6, IL-8, IL-10, and IL-12 were measured by flow cytometry. Lung hyperinflation significantly increased (P < 0.05) all measured cytokines (TNF-alpha: 1.2 +/- 3.8 vs 6.4 +/- 8.6 pg/mL; IL-1beta: 4.9 +/- 15.6 vs 22.4 +/- 28.4 pg/mL; IL-6: 1.4 +/- 3.3 vs 6.5 +/- 5.6 pg/mL; IL-8: 13.2 +/- 8.8 vs 33.4 +/- 26.4 pg/mL; IL-10: 3.3 +/- 3.3 vs 7.7 +/- 6.5 pg/mL, and IL-12: 3.1 +/- 7.9 vs 9 +/- 11.4 pg/mL), which returned to basal levels 12 h later. A significant correlation was found between changes in pro- (IL-6) and anti-inflammatory (IL-10) cytokines (r = 0.89, P = 0.004). LHM-induced lung stretching was associated with an early inflammatory response in healthy spontaneously breathing subjects.