Neurotrophins and Trk receptors in the developing and adult ovary of Coturnix coturnix japonica.

NGF, BDNF, NT-3 and their specific receptors TrkA, TrkB and TrkC are known to be involved in the development and maintenance of vertebrates' nervous system. However, these molecules play a role also in non-neuronal tissue, such as in the reproductive system. In this study we investigated the presence and localization of neurotrophins and Trk receptors to unravel their potential role in the developing and adult ovary of Japanese quail, a model species well suited for reproduction studies. Western blotting analysis on ovaries of three month old quails in the period of egg laying showed the presence of pro and mature forms of neurotrophins and splice variants of Trk receptors. Immunohistochemical investigation reported that in embryonic ovaries from the 9th day of incubation to the hatching NGF and NT-3 were observed in the cortical and medullar areas respectively, whereas Trk receptors were observed in both areas. In adult ovary, all NTs were detected in glandular stromal cells, NGF and NT-3 also in the nervous component. Regarding follicle components, NGF and BDNF were observed in oocytes and follicular cells. All TrK receptors were present in nervous components and only TrkA in glandular stromal cells. In follicles, TrkA was present in oocyte cytoplasm and TrkB in theca cells. The results suggest an involvement of the neurotrophin system in the quail ovary physiology, promoting the oocyte development and follicular organization in the embryo, as well as oocyte and follicular maturation in adults.

Sigma 2 receptor expression levels in blood and bladder from healthy and bladder cancer cattle.

The expression of sigma-2 receptor (S2R) was assayed in blood and bladder samples from healthy cattle and in blood and bladder of cattle with deltapapillomavirus-associated urothelial tumors. Samples of bladder from cattle with neoplasia had significantly higher S2R than samples of bladder from healthy cattle (95% CI 0.31-0.82, P < 0.05). In addition, significantly higher S2R was detected in the blood of cattle with bladder cancer than blood from healthy cattle (95% CI 0.22-0.41, P < 0.05). The results provide evidence that increased expression of SR2 in blood could be useful as circulating biomarker for bladder cancer in cattle. PGRMC1 protein levels were also found to be increased in blood and bladder from cattle with cancer and increased expression of PGRMC1 transcripts was detected by quantitative real time PCR in samples from cattle neoplasia. Furthermore, electron microscopy revealed phagophores and numerous autophagosomes, ultrastructural hallmark of autophagy.

Glutathione concentration and gamma-glutamyltransferase activity in water buffalo colostrum.

Evidence is presented that the buffalo mammary gland contains enzymes that catalyse the synthesis and utilization of glutathione. A significant, inverse correlation (r = 0.79) was detected between colostrum gamma-glutamyltransferase (GGT) and glutathione (GSH), suggesting that the enzyme uses GSH as a substrate for its activity. A similar trend was shown in mammary gland homogenates (r = 0.75). Our results show that GSH is secreted into buffalo colostrum and suggest that the enzyme GGT degrades it. To the authors' knowledge, this is the first demonstration of the involvement of GGT-mediated GSH metabolism in the synthesis of colostrums, which elucidates the role of the enzyme that has always been reported very high in colostrum.

The pharmacologic basis of treatment with colchicine in children with familial Mediterranean fever.

Familial Mediterranean fever (FMF) is the prototype of auto-inflammatory disorders and is ethnically restricted to people living in the Mediterranean basin and Middle-East. Pyrin, the protein product of the FMF gene, expressed in myeloid cells and fibroblasts, interacts with the cytoskeletal machinery and may modulate leukocyte effector functions. At present colchicine, an alkaloid with antimitotic activity interfering with microtubule formation, which has been used to alleviate acute gout, is the only available drug for patients with FMF to prevent both acute attacks and long-term complications such as amyloidosis. The anti-inflammatory effect of colchicine may be mediated not only through direct interaction with microtubules, but also through changes at the transcriptional level influencing cell cycle regulation and leukocyte migration. Gastrointestinal side effects may occur early and are the most frequent manifestations of colchicine toxicity in children, whilst multiple organ failure is very rarely reported as overdosage expression.

Evaluation of adenosine 5'-diphosphate (ADP)- and collagen-induced platelet aggregation in canine leishmaniasis.

Leishmania-infected dogs, which represent an important reservoir of infection in many parts of the world, frequently suffer from haematological disorders, including thrombocytopenia. In this study, the ability of platelets from healthy (control) dogs (n = 11) and from dogs with naturally acquired clinical leishmaniasis (n = 24) to aggregate in the presence of two different agonists (adenosine 5'-diphosphate [ADP] and collagen) was assayed. Haematological parameters examined consisted of the platelet count, prothrombin time, activated partial thromboplastin time (aPTT), fibrinogen concentration and D-dimer concentration. In dogs with leishmaniasis, a significant decrease in ADP- and collagen-induced platelet aggregation was observed. Compared with platelets from the control dogs, those from leishmania-infected dogs showed a higher sensitivity to collagen, as demonstrated by a reduction in platelet aggregation of up to 20.4%, and a significant (P < 0.0001) difference for all the doses tested. With ADP the reduction was up to 10.4%, the difference reaching a significant level of P < 0.0001 only at the maximum dose used. The nature of this response, which was not accompanied by any clinical signs of bleeding other than an increase in aPTT, emphasizes the role of platelets in the parasite-host cell interaction.

Adhesive properties of platelets from different animal species.

The use of large animals (e.g., pig and sheep) in human medicine, and the need to develop new therapeutic strategies for domestic animal diseases related to platelet disorders, require better characterization of the physiology of animal platelets. In this study, the ability of platelets from buffaloes, horses, pigs and sheep to adhere to immobilized autologous fibrinogen was compared with that of human platelets. Blood samples were collected from the jugular vein of six healthy subjects of each species and platelet-rich plasma (PRP) was obtained by centrifugation. Platelets, isolated by further centrifugation of PRP, were washed by gel-filtration on Sepharose-2B, counted and added to the wells of 96-well plates pre-coated with autologous fibrinogen. After different times of incubation, non-adherent platelets were removed, and the number of adherent platelets was assessed by measuring endogenous acid phosphatase activity. Horse platelets showed the strongest ability to adhere to autologous immobilized fibrinogen, being 1.7-, 3.1- and 2.3-fold more active than human, buffalo and porcine platelets, respectively. Sheep platelets were unable to adhere to autologous immobilized fibrinogen. Platelet activation by adenosine 5-diphosphate (ADP) increased both human and animal platelet adhesive response. ADP-stimulated sheep platelets were able to adhere to autologous immobilized fibrinogen, albeit to a lesser extent than platelets from the other animal species. The observed interspecies variability in adhesive properties of platelets may reflect structural differences, or differences in the availability of the fibrinogen receptor (glycoprotein IIb/IIIa) on the platelet surface.

Species variability in platelet aggregation response to different agonists.

Conflicting data on platelet function in animal species are reported in the literature. In this study, the response of buffalo, horse, pig and sheep platelets to different agonists was assessed. Blood samples were collected from the jugular vein of six healthy subjects of each species and platelet-rich plasma was obtained by centrifugation. Platelet aggregation responses to increasing doses of adenosine 5'-diphosphate (ADP), arachidonic acid, collagen, platelet activating factor (PAF) and ristocetin were measured by a turbidimetric method. Horse platelets were the most responsive to ADP, collagen and PAF, whereas sheep platelets were the most responsive to ristocetin. The response to arachidonic acid varied least between species. PAF was the most effective agonist, inducing a maximum aggregation response at a concentration of 1 micro M for platelets of each species. Conversely, concentrations of ristocetin higher than 1mg/ml induced a maximum aggregation response only with sheep and horse platelets. The different responses of platelets from the four animal species to various agonists may reflect either (1). structural differences (including composition of the platelet membrane and presence of specific agonist receptors), or (2). activation of distinct signalling pathways by the agonist.

Modulation of anthracycline activity in canine mammary tumour cells in vitro by medroxyprogesterone acetate.

Failure of chemotherapy with anthracyclines as a result of drug resistance and toxicity is a major problem in the clinical management of neoplasia. The aim of the present study was to evaluate the activity of medroxyprogesterone acetate (MPA) as a chemosensitiser on anthracycline cytotoxicity. The study investigated whether such an effect could be related to an increase in lipid peroxidation, nitric oxide production, membrane fluidity and intracellular anthracycline concentration. The results showed that anthracyclines decreased nitric oxide production but increased membrane viscosity (polarisation constant) and lipid hydroperoxide formation in canine mammary tumour cells. Moreover, it was found that both drug-induced cytotoxicity and membrane viscosity increased in the presence of MPA. Conversely, lipid hydroperoxides decreased in MPA-supplemented cells. Medroxyprogesterone acetate did not show any effect on nitric oxide production. The two anthracyclines used (doxorubicin and idarubicin) showed differential intranuclear accumulation in canine mammary tumour cells, and MPA significantly modified intracellular concentration of anthracyclines.

Ovarian function suppression with a GnRH analogue: D-ser(But[t])[6]-Arzgly[10]-LHRH (Goserelin) in hormone dependent canine mammary cancer.

Hormones and hormone level modifying substances have long been used to treat hormone-dependent tumours in humans. Recently, attempts have been made to use hormone manipulation regimens for the treatment of these tumours in veterinary medicine. The aim of the present study was to evaluate the activity of the luteinizing hormone-releasing hormone (LHRH)-agonist, D-ser(But[t])[6]-Azgly[10]-LHRH (Goserelin) in hormone-dependent mammary cancer in dogs. Eighteen female dogs with hormone-dependent mammary cancer (T2-T4, N0, M0 according to TNM clinical staging classification) were selected and allocated into two groups: nine dogs not treated with Goserelin (Group 1) referred to as control; and nine dogs treated with 60 microg/kg depot Goserelin every 21 days for 12 months (Group 2). Goserelin treatment decreased circulating levels of oestradiol and progesterone and reduced the size of mammary tumours; all the animals showed objective response (OR) to treatment after 3 months, and the relapse-free survival after 2 years was 88%. Haematology and blood chemistry parameters, measured every month from the beginning of treatment, as well as physical examination, showed that the drug was without toxic effects. This suggests that, at the dose administered, Goserelin blocks the hypothalamus-pituitary-ovary axis, and consequently can be useful to treat hormone-dependent mammary tumours in female dogs.

Preliminary observations on the interference of antiblastic agents in membrane fluidity and leukocyte potential.

A major problem in cancer treatment is the progressive desensitization of the cancer cells to chemotherapeutic drugs. Several hypotheses have been advanced to explain this property of neoplastic cells. In recent years, some calcium-channel blockers have successfully been used to restore drug-sensitivity in previously resistant tumors. The presence of a correlation between ion channels and membrane fluidity is well known. In the ambit of our studies on the activity of several chemotherapeutic drugs on tumors, we have studied the variations in membrane depolarization and fluidity in some leukemic cells as a result of polychemotherapeutic treatments. Our results demonstrate that the membrane fluidity and K(+)-induced depolarization of some types of leukemic cells in patients untreated and treated with some chemotherapeutic agents, are altered significantly as compared to those of normal leukocytes.