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1.
Artigo em Inglês | MEDLINE | ID: mdl-34562624

RESUMO

Ambush-foraging snakes that ingest large meals might undergo several months without eating when they use the internal reserves to support the energetic costs of living. Then, morphological and physiological processes might be orchestrated during the transition from fasting to the postprandial period to rapidly use the energetic stores while the metabolic rate is elevated in response to food intake. To understand the patterns of substrates deposition after feeding, we accessed the morphological and biochemical response in Boa constrictor snakes after two months of fasting and six days after feeding. We followed the plasma levels of glucose, total proteins, and total lipids, and we performed the stereological ultrastructural analysis of the liver and the proximal region of the intestine to quantify glycogen granules and lipid droplets. In the same tissues and stomach, we measured the activity of the enzyme fructose-1,6-biphosphatase (FBPase1) involved in the gluconeogenic pathway, and we measured pyruvate kinase (PK) and lactate dehydrogenase (LDH) enzymatic activities involved in the anaerobic pathway in the liver. Briefly, our results indicated an increase in boas' plasma glucose one day after meal intake compared to unfed snakes. The hepatic glycogen reserves were continuously restored within days after feeding. Also, the enzymes involved in the energetic pathways increased activity six days after feeding in the liver. These findings suggest a quick restoring pattern of energetic stores during the postprandial period.


Assuntos
Boidae/fisiologia , Animais , Glicemia/metabolismo , Proteínas Sanguíneas/metabolismo , Boidae/sangue , Ingestão de Alimentos/fisiologia , Metabolismo Energético , Comportamento Alimentar/fisiologia , Gluconeogênese , Homeostase , Intestinos/metabolismo , Intestinos/ultraestrutura , Lipídeos/sangue , Fígado/metabolismo , Fígado/ultraestrutura , Glicogênio Hepático/metabolismo , Microscopia Eletrônica de Transmissão , Período Pós-Prandial/fisiologia
2.
J Zoo Wildl Med ; 51(2): 350-356, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549564

RESUMO

Reptarenaviruses infect a variety of boid and pythonid snake species worldwide and have been shown to be the cause of inclusion body disease (IBD). Little is known about the correlations between virus infection and clinical disease, as well as the effects of viral infection on the immune system and the blood protein fractions. The goal of this study was to examine the differences in the plasma protein fractions in reptarenavirus reverse transcription polymerase chain reaction (RT-PCR)-negative and -positive tested snakes with and without clinical signs of disease. Blood from a total of 111 boa constrictors (Boa constrictor) was evaluated. Reverse transcription PCRs and H&E staining for inclusion bodies were carried out on each sample for the detection of reptarenavirus, and the plasma protein fractions were evaluated by capillary zone electrophoresis (CZE). Thirty four of the 111 evaluated snakes were positive by RT-PCR and 19 of the 34 showed clinical signs of disease. In comparison with IBD-negative healthy boa constrictors, the positive snakes with clinical signs had significantly lower albumin levels (P = 0.0052), lower A: G ratios (P = 0.0037), and lower α-globulin levels (P = 0.0073), while their γ-globulin levels were significantly higher (P = 0.0004). In the same comparison, clinically healthy arenavirus-positive boas showed only significantly lower α-globulin (P = 0.0124) and higher γ-globulin levels (P = 0.0394). The results of the present study indicate that reptarenavirus infection may influence plasma protein fractions in boa constrictors.


Assuntos
Infecções por Arenaviridae/virologia , Arenaviridae/fisiologia , Boidae/sangue , Eletroforese Capilar/veterinária , Animais , Valores de Referência
3.
Anticancer Agents Med Chem ; 20(13): 1558-1570, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32364082

RESUMO

BACKGROUND: Cancer contributes to significant morbidity and mortality despite advances in treatment and supportive care. There is a need for the identification of effective anticancer agents. Reptiles such as tortoise, python, and water monitor lizards are exposed to heavy metals, tolerate high levels of radiation, feed on rotten/germ-infested feed, thrive in unsanitary habitat and yet have prolonged lifespans. Such species are rarely reported to develop cancer, suggesting the presence of anticancer molecules/mechanisms. METHODS: Here, we tested effects from sera of Asian water monitor lizard (Varanus salvator), python (Malayopython reticulatus) and tortoise (Cuora kamaroma amboinensis) against cancer cells. Sera were collected and cytotoxicity assays were performed using prostate cancer cells (PC3), Henrietta Lacks cervical adenocarcinoma cells (HeLa) and human breast adenocarcinoma cells (MCF7), as well as human keratinized skin cells (Hacat), by measuring lactate dehydrogenase release as an indicator for cell death. Growth inhibition assays were performed to determine the effects on cancer cell proliferation. Liquid chromatography mass spectrometry was performed for molecular identification. RESULTS: The findings revealed that reptilian sera, but not bovine serum, abolished viability of Hela, PC3 and MCF7 cells. Samples were subjected to liquid chromatography mass spectrometry, which detected 57 molecules from V. salvator, 81 molecules from Malayopython reticulatus and 33 molecules from C. kamaroma amboinensis and putatively identified 9 molecules from V. salvator, 20 molecules from Malayopython reticulatus and 9 molecules from C. kamaroma amboinensis when matched against METLIN database. Based on peptide amino acid composition, binary profile, dipeptide composition and pseudo-amino acid composition, 123 potential Anticancer Peptides (ACPs) were identified from 883 peptides from V. salvator, 306 potential ACPs from 1074 peptides from Malayopython reticulatus and 235 potential ACPs from 885 peptides from C. kamaroma amboinensis. CONCLUSION: To our knowledge, for the first time, we reported comprehensive analyses of selected reptiles' sera using liquid chromatography mass spectrometry, leading to the identification of potentially novel anticancer agents. We hope that the discovery of molecules from these animals will pave the way for the rational development of new anticancer agents.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/sangue , Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/sangue , Antineoplásicos/química , Boidae/sangue , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lagartos/sangue , Estrutura Molecular , Relação Estrutura-Atividade , Tartarugas/sangue
4.
PLoS One ; 15(2): e0229657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32106235

RESUMO

Plasma in several organisms has components that promote resistance to envenomation by inhibiting specific proteins from snake venoms, such as phospholipases A2 (PLA2s). The major hypothesis for inhibitor's presence would be the protection against self-envenomation in venomous snakes, but the occurrence of inhibitors in non-venomous snakes and other animals has opened new perspectives for this molecule. Thus, this study showed for the first time the structural and functional characterization of the PLA2 inhibitor from the Boa constrictor serum (BoaγPLI), a non-venomous snake that dwells extensively the Brazilian territory. Therefore, the inhibitor was isolated from B. constrictor serum, with 0.63% of recovery. SDS-PAGE showed a band at ~25 kDa under reducing conditions and ~20 kDa under non-reducing conditions. Chromatographic analyses showed the presence of oligomers formed by BoaγPLI. Primary structure of BoaγPLI suggested an estimated molecular mass of 22 kDa. When BoaγPLI was incubated with Asp-49 and Lys-49 PLA2 there was no severe change in its dichroism spectrum, suggesting a non-covalent interaction. The enzymatic assay showed a dose-dependent inhibition, up to 48.2%, when BoaγPLI was incubated with Asp-49 PLA2, since Lys-49 PLA2 has a lack of enzymatic activity. The edematogenic and myotoxic effects of PLA2s were also inhibited by BoaγPLI. In summary, the present work provides new insights into inhibitors from non-venomous snakes, which possess PLIs in their plasma, although the contact with venom is unlikely.


Assuntos
Boidae/sangue , Fosfolipases A2 do Grupo IV/antagonistas & inibidores , Inibidores de Fosfolipase A2/sangue , Sequência de Aminoácidos , Animais , Bothrops/metabolismo , Brasil , Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/química , Fosfolipases A2 do Grupo IV/química , Peso Molecular , Inibidores de Fosfolipase A2/química , Domínios e Motivos de Interação entre Proteínas , Venenos de Serpentes/antagonistas & inibidores , Venenos de Serpentes/química , Espectrometria de Massas em Tandem
5.
Gen Comp Endocrinol ; 288: 113375, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874136

RESUMO

Plasma corticosterone (CORT) concentrations fluctuate in response to homeostatic demands. CORT is widely recognized as an important hormone related to energy balance. However, far less attention has been given to the potential role of CORT in regulating salt and water balance or responding to osmotic imbalances. We examined the effects of reproductive and hydric states on CORT levels in breeding Children's pythons (Antaresia childreni), a species with substantial energetic and hydric costs associated with egg development. Using a 2 × 2 experimental design, we examined how reproduction and water deprivation, both separately and combined, impact CORT levels and how these changes correlate with hydration (plasma osmolality) and energy levels (blood glucose). We found that reproduction leads to increased CORT levels, as does dehydration induced by water deprivation. The combined impact of reproduction and water deprivation led to the largest increases in CORT levels. Additionally, we found significant positive relationships among CORT levels, plasma osmolality, and blood glucose. Our results provide evidence that both reproductive activity and increased plasma osmolality can lead to increased plasma CORT in an ectotherm, which could be explained by either CORT having a role as a mineralocorticoid or CORT being elevated as part of a stress response to resource imbalances.


Assuntos
Boidae/metabolismo , Corticosterona/sangue , Reprodução/fisiologia , Privação de Água/fisiologia , Animais , Boidae/sangue , Boidae/fisiologia , Desidratação/sangue , Desidratação/metabolismo , Desidratação/fisiopatologia , Feminino , Masculino , Osmorregulação/fisiologia
6.
J Vet Pharmacol Ther ; 42(6): 722-731, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31469454

RESUMO

Midazolam is a benzodiazepine with sedative, muscle relaxant, anxiolytic, and anticonvulsant effects. Twelve ball pythons (Python regius) were used in a parallel study evaluating the pharmacokinetics of 1 mg/kg midazolam following a single intracardiac (IC) or intramuscular (IM) administration. Blood was collected from a central venous catheter placed 7 days prior, or by cardiocentesis, at 15 time points starting just prior to and up to 72 hr after drug administration. Plasma concentrations of midazolam and 1-hydroxymidazolam were determined by the use of high-performance liquid chromatography tandem-mass spectrometry and pharmacokinetic parameters were estimated using noncompartmental analysis. The mean ± SD terminal half-lives of IC and IM midazolam were 12.04 ± 3.25 hr and 16.54 ± 7.10 hr, respectively. The area under the concentration-time curve extrapolated to infinity, clearance, and apparent volume of distribution in steady-state of IC midazolam were 19,112.3 ± 3,095.9 ng*hr/ml, 0.053 ± 0.008 L hr-1  kg-1 , and 0.865 ± 0.289 L/kg, respectively. The bioavailability of IM midazolam was estimated at 89%. Maximum plasma concentrations following an IM administration were reached 2.33 ± 0.98 hr and 24.00 ± 14.12 hr postinjection for midazolam and 1-hydroxymidazolam, respectively, and 22.33 ± 20.26 hr postinjection for 1-hydroxymidazolam following IC administration.


Assuntos
Boidae/sangue , Midazolam/análogos & derivados , Midazolam/farmacocinética , Animais , Área Sob a Curva , Cateteres Venosos Centrais/veterinária , Meia-Vida , Hipnóticos e Sedativos , Injeções Intramusculares , Midazolam/sangue , Midazolam/metabolismo
7.
J Exp Zool A Ecol Integr Physiol ; 331(4): 245-252, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30873745

RESUMO

Dehydration is considered a physiological challenge, and many organisms live in environments that undergo periods of reduced water availability that can lead to dehydration. Recent studies have found a positive relationship between dehydration and innate immune function in animals adapted to xeric or semixeric environments. To explore the generality of this relationship, we examined the impact of dehydration on innate immune performance in water pythons (Liasis fuscus), a semiaquatic snake from the wet-dry tropics of Australia. We collected blood samples from male and female water pythons held in the laboratory without food and water for 4 weeks. We also collected blood from free-ranging snakes throughout the Austral dry-season. We evaluated plasma osmolality and innate immune function (agglutination, lysis, and bacterial-killing ability) and found that increased osmolality, whether manipulated in the laboratory or as a result of natural water limitation, resulted in enhanced aspects of innate immune performance. Counter-intuitively, snakes in the wild became more hydrated as the dry season progressed, suggesting the dehydrated snakes move to water sources periodically to rehydrate. Comparing our data with those from previous studies, we suspect species divergence in the level of dehydration (i.e., hyperosmolality) that triggers enhanced immune capabilities.


Assuntos
Boidae/imunologia , Desidratação/imunologia , Imunidade Inata/fisiologia , Animais , Austrália , Boidae/sangue , Boidae/fisiologia , Feminino , Masculino , Concentração Osmolar , Plasma/química
8.
J Zoo Wildl Med ; 49(3): 810-812, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30212358

RESUMO

Deficiency of vitamin D can contribute to health complications that present as metabolic bone disease. The aim of this small-scale study was to determine if a high UVb irradiance would affect an increase in plasma vitamin D3 concentrations in Burmese pythons ( Python bivittatus). There have been inconsistent results throughout the literature concerning the usefulness of UVb radiation regarding vitamin D3 synthesis. Blood samples of four healthy Burmese pythons were taken at day 0 and day 310. After the first blood sample was taken, an Arcadia Superzoo T5 ASZ01 lamp was fitted in the enclosure. For 310 days, the pythons were exposed to UVb radiation. Blood plasma vitamin D3 concentrations were considerably higher after UVb exposure. This study indicates that a period of 10 mo of UVb exposure can result in an increased vitamin D3 status in Burmese pythons. Answering whether these elevated levels have health benefits for Burmese pythons (and possibly other snake species) requires further studies.


Assuntos
Boidae/sangue , Calcifediol/sangue , Raios Ultravioleta , Animais , Feminino , Masculino
9.
Vet Clin Pathol ; 47(3): 407-414, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30088675

RESUMO

BACKGROUND: Blood centrifugation and buffy coats are at the cornerstone of hematology. In mammals, the buffy coat has a layered disposition (from bottom to top) with neutrophils on top of erythrocytes, followed by monocytes/lymphocytes, and platelets. In nonmammals, this distribution is unknown. Recently, the cell tube block (CTB) technique was developed to study the buffy coat, but it was never applied to nonmammal buffy coats. OBJECTIVES: This study aimed to evaluate using the CTB technique to study reptilian and avian buffy coats and to propose its use for clinical applications. METHODS: Blood from five birds and eight reptiles of different species was obtained to make CTBs that were processed for optical/electron microscopy. H&E, Sirius red, and immunohistochemistry staining against CD3 (to label T lymphocytes) were applied to the CTBs. RESULTS: In birds, the buffy coat had a layered appearance with the granulocyte layer containing granulocytes (heterophils and eosinophils) and nucleated erythrocytes followed by a mononuclear cell layer containing lymphocytes, monocytes, and thrombocytes. In some animals, a nucleated erythrocyte layer was observed admixed with the granulocyte/mononuclear cell layer. A small clot within the buffy coat was seen in seven reptiles, and less definition of layers occurred in reptiles, with only one or two layers. Lymphocytes appeared toward the top of the buffy coat. CONCLUSIONS: From a comparative hematology perspective, the buffy coat of mammals differs from that of birds and more from that of reptiles. The CTB technique can be used to study these differences in avian and reptilian hematology, especially to study atypical circulating cells, hemoparasites, or blood cell proportions in health and disease.


Assuntos
Aves/sangue , Buffy Coat/ultraestrutura , Répteis/sangue , Animais , Plaquetas/ultraestrutura , Boidae/sangue , Eritrócitos/ultraestrutura , Falconiformes/sangue , Iguanas/sangue , Lagartos/sangue , Linfócitos/ultraestrutura , Microscopia/veterinária , Microscopia Eletrônica/veterinária , Monócitos/ultraestrutura , Tartarugas/sangue
10.
Vet Clin Pathol ; 45(2): 271-80, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27213293

RESUMO

BACKGROUND: The reptilian immune system is represented by innate, humoral, and cell-mediated mechanisms, involving different types of blood leukocytes. The development of optimized methods for the advanced study of origin and function of reptilian blood leukocytes is needed. OBJECTIVES: The purpose of the study was to optimize leukocyte density gradient isolation protocols from snake peripheral blood samples, and characterize recovered cells by flow cytometry based on size and internal complexity for a qualitative and semi-quantitative assessment of leukocyte populations in one boa (Boa constrictor), and 2 viper species (Bothrops jararaca, Crotalus durissus). METHODS: Blood samples from 30 snakes (10 from each species, 5 males and 5 females) were collected in tubes with sodium heparin. Fresh blood was centrifuged with either ficoll-paque PLUS or percoll density gradients for leukocyte isolation. Flow cytometric leukocyte gates were defined based on size (forward scatter [FSC]) and internal complexity (side scatter [SSC]). Relative leukocyte differential counts after sorting the cells in these gates in one snake for each species were compared to conventional light microscopic differential counts on unsorted isolated leukocytes. RESULTS: There was no statistical difference in the relative leukocyte populations, including heterophils, azurophils, and small and large lymphocytes between samples isolated by ficoll or percoll. Four leukocyte gates were identified based on their location in FSC/SSC cytograms. The relative leukocyte differential counts after sorting in single animals showed some agreement with the light microscopy differential count on unsorted cells. CONCLUSIONS: Based on FSC and SSC, 4 distinct leukocyte populations were found in ficoll or percoll density gradient isolated leukocytes from peripheral blood from boa and viper species. Further optimization of the technique should allow the performance of functional assays.


Assuntos
Boidae/sangue , Bothrops/sangue , Crotalus/sangue , Citometria de Fluxo/veterinária , Leucócitos , Animais , Feminino , Citometria de Fluxo/métodos , Masculino
11.
Artigo em Inglês | MEDLINE | ID: mdl-26005204

RESUMO

Carbonic anhydrase (CA) is one of the most abundant proteins found in vertebrate erythrocytes with the majority of species expressing a low activity CA I and high activity CA II. However, several phylogenetic gaps remain in our understanding of the expansion of cytoplasmic CA in vertebrate erythrocytes. In particular, very little is known about isoforms from reptiles. The current study sought to characterize the erythrocyte isoforms from two squamate species, Python molurus and Nerodia rhombifer, which was combined with information from recent genome projects to address this important phylogenetic gap. Obtained sequences grouped closely with CA XIII in phylogenetic analyses. CA II mRNA transcripts were also found in erythrocytes, but found at less than half the levels of CA XIII. Structural analysis suggested similar biochemical activity as the respective mammalian isoforms, with CA XIII being a low activity isoform. Biochemical characterization verified that the majority of CA activity in the erythrocytes was due to a high activity CA II-like isoform; however, titration with copper supported the presence of two CA pools. The CA II-like pool accounted for 90 % of the total activity. To assess potential disparate roles of these isoforms a feeding stress was used to up-regulate CO2 excretion pathways. Significant up-regulation of CA II and the anion exchanger was observed; CA XIII was strongly down-regulated. While these results do not provide insight into the role of CA XIII in the erythrocytes, they do suggest that the presence of two isoforms is not simply a case of physiological redundancy.


Assuntos
Boidae/sangue , Anidrases Carbônicas/química , Anidrases Carbônicas/metabolismo , Eritrócitos/enzimologia , Sequência de Aminoácidos , Animais , Transporte Biológico , Boidae/genética , Boidae/metabolismo , Boidae/fisiologia , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/genética , Citoplasma/enzimologia , Ingestão de Alimentos , Eritrócitos/citologia , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Dados de Sequência Molecular , Filogenia , Análise de Sequência , Transcrição Gênica
12.
Artigo em Inglês | MEDLINE | ID: mdl-25088182

RESUMO

Precise measurements of blood gases and pH are of pivotal importance to respiratory physiology. However, the traditional electrodes that could be calibrated and maintained at the same temperature as the experimental animal are increasingly being replaced by new automated blood gas analyzers. These are typically designed for clinical use and automatically heat the blood sample to 37°C for measurements. While most blood gas analyzers allow for temperature corrections of the measurements, the underlying algorithms are based on temperature-effects for human blood, and any discrepancies in the temperature dependency between the blood sample from a given species and human samples will bias measurements. In this study we review the effects of temperature on blood gases and pH and evaluate the performance of an automated blood gas analyzer (GEM Premier 3500). Whole blood obtained from pythons and freshwater turtles was equilibrated in rotating Eschweiler tonometers to a variety of known P(O2)'s and P(CO2)'s in gas mixtures prepared by Wösthoff gas mixing pumps and blood samples were measured immediately on the GEM Premier 3500. The pH measurements were compared to measurements using a Radiometer BMS glass capillary pH electrode kept and calibrated at the experimental temperature. We show that while the blood gas analyzer provides reliable temperature-corrections for P(CO2) and pH, P(O2) measurements were substantially biased. This was in agreement with the theoretical considerations and emphasizes the need for critical calibrations/corrections when using automated blood gas analyzers.


Assuntos
Boidae/sangue , Dióxido de Carbono/sangue , Modelos Biológicos , Oxigênio/sangue , Fisiologia Comparada/métodos , Fenômenos Fisiológicos Respiratórios , Tartarugas/sangue , Algoritmos , Métodos Analíticos de Preparação de Amostras/veterinária , Animais , Automação Laboratorial , Gasometria/instrumentação , Gasometria/veterinária , Calibragem , Dinamarca , Água Doce , Temperatura Alta/efeitos adversos , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Especificidade da Espécie
13.
J Exp Biol ; 217(Pt 10): 1784-9, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24311803

RESUMO

Physiological cardiac hypertrophy is characterized by reversible enlargement of cardiomyocytes and changes in chamber architecture, which increase stroke volume and via augmented convective oxygen transport. Cardiac hypertrophy is known to occur in response to repeated elevations of O2 demand and/or reduced O2 supply in several species of vertebrate ectotherms, including postprandial Burmese pythons (Python bivittatus). Recent data suggest postprandial cardiac hypertrophy in P. bivittatus is a facultative rather than obligatory response to digestion, though the triggers of this response are unknown. Here, we hypothesized that an O2 supply-demand mismatch stimulates postprandial cardiac enlargement in Burmese pythons. To test this hypothesis, we rendered animals anemic prior to feeding, essentially halving blood oxygen content during the postprandial period. Fed anemic animals had heart rates 126% higher than those of fasted controls, which, coupled with a 71% increase in mean arterial pressure, suggests fed anemic animals were experiencing significantly elevated cardiac work. We found significant cardiac hypertrophy in fed anemic animals, which exhibited ventricles 39% larger than those of fasted controls and 28% larger than in fed controls. These findings support our hypothesis that those animals with a greater magnitude of O2 supply-demand mismatch exhibit the largest hearts. The 'low O2 signal' stimulating postprandial cardiac hypertrophy is likely mediated by elevated ventricular wall stress associated with postprandial hemodynamics.


Assuntos
Boidae/sangue , Boidae/fisiologia , Oxigênio/sangue , Anemia/sangue , Anemia/complicações , Animais , Cardiomegalia/sangue , Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Digestão , Jejum , Coração/fisiologia , Coração/fisiopatologia , Frequência Cardíaca , Período Pós-Prandial
14.
Vet Rec ; 173(14): 345, 2013 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-24068697

RESUMO

Despite the popularity of keeping snakes in captivity, there has been limited investigation into the effects of UV radiation on vitamin D levels in snakes. The aim of this study was to investigate the effects of UV-b radiation on plasma 25-hydroxyvitamin D3 levels and ionised calcium concentrations in ball pythons (Python regius). Blood samples were taken from 14 ball pythons, which had never been exposed to UV-b light, to obtain baseline 25-hydroxyvitamin D3 levels and ionised calcium concentrations. Blood samples were then taken again from the same snakes 70 days later after one group (Group 1, n=6 females) were exposed to UV-b radiation daily, and the other group (Group 2, n=5 males and 3 females) were exposed to no UV-b radiation. Mean±sd 25-hydroxyvitamin D3 levels on day 0 in Group 1 were 197±35 nmol/l, and on day 70 were 203.5±13.8 nmol/l. Mean±sd 25-hydroxyvitamin D3 levels in Group 2 on day 0 were 77.7±41.5 nmol/l, and on day 70 were 83.0±41.9 nmol/l. Mean±sd ionised calcium levels at day 0 were 1.84±0.05 mmol/l for Group 1, and on day 70 were 1.78±0.07 mmol/l. Mean±sd ionised calcium levels at day 0 were 1.79±0.07 mmol/l for Group 2, and on day 70 were 1.81±0.05 mmol/l. No association was demonstrated between exposure to UV-b radiation and plasma 25-hydroxyvitamin D3 and ionised calcium concentrations. These results may provide baseline parameters for future studies in this and other snake species to determine ability to utilise UV-b light for vitamin D production.


Assuntos
Boidae/metabolismo , Calcifediol/efeitos da radiação , Cálcio/efeitos da radiação , Raios Ultravioleta , Animais , Animais de Zoológico , Boidae/sangue , Calcifediol/sangue , Cálcio/metabolismo , Feminino , Masculino
15.
Braz. j. vet. res. anim. sci ; 50(6): 497-498, 2013. tab
Artigo em Português | LILACS | ID: lil-789913

RESUMO

It was determined the average values of the following blood biochemical indicators of boas (Boa constrictor): glucose, urea, creatinine, aspartate aminotransferase (AST), alanine transaminase (ALT), amylase and lipase, and compared the results obtained concerning sex. A total of 12 Boa constrictor specimens were used, seven males and five females. The average of the biochemical indicators between males and females had no significant difference. The traditional biochemical techniques have been useful to determine these indicators to this species...


Foram determinados os valores médios dos indicadores bioquímicos sanguíneos: glicose, ureia, creatinina, aspartato aminotransferase (AST), alanina aminotransferase (ALT), amilase e lipase de jiboias (Boa constrictor) e comparados os valores das concentrações encontradas entre os grupos de machos e fêmeas. Foram utilizados 12 espécimes de Boa constrictor, dos quais sete machos e cinco fêmeas. A comparação das médias dos indicadores bioquímicos entre os grupos de machos e fêmeas indicou ausência de influência significativa de fatores sexuais. As técnicas bioquímicas tradicionais foram adequadas para a determinação desses indicadores para esta espécie...


Assuntos
Animais , Alanina Transaminase/sangue , Amilases/sangue , Aspartato Aminotransferases/sangue , Boidae/sangue , Creatinina/sangue , Glicemia/análise , Lipase/sangue , Ureia/sangue , Análise Química do Sangue/veterinária , Padrões de Referência
16.
J Wildl Dis ; 48(2): 282-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22493104

RESUMO

Despite increased worldwide popularity of keeping reptiles as pets, we know little about hematologic and biochemical parameters of most reptile species, or how these measures may be influenced by intrinsic and extrinsic factors. Blood samples from 43 wild-caught pythons (Morelia spilota imbricata) were collected at various stages of a 3-yr ecological study in Western Australia. Reference intervals are reported for 35 individuals sampled at the commencement of the study. As pythons were radiotracked for varying lengths of time (radiotransmitters were surgically implanted), repeated sampling was undertaken from some individuals. However, because of our ad hoc sampling design we cannot be definitive about temporal factors that were most important or that exclusively influenced blood parameters. There was no significant effect of sex or the presence of a hemogregarine parasite on blood parameters. Erythrocyte measures were highest for pythons captured in the jarrah forest and at the stage of radiotransmitter implantation, which was also linked with shorter time in captivity. Basophil count, the only leukocyte influenced by the factors tested, was highest when the python was anesthetized, as was globulin concentration. Albumin and the albumin:globulin ratio were more concentrated in summer (as was phosphorous) and at the initial stage of radiotransmitter placement (as was calcium). No intrinsic or extrinsic factors influenced creatinine kinase, aspartate aminotransferase, uric acid, or total protein. This study demonstrates that factors including season, location, surgical radiotransmitter placement, and anesthetic state can influence blood parameters of M. s. imbricata. For accurate diagnosis, veterinarians should be aware that the current reference intervals used to identify the health status of individuals for this species are outdated and the interpretation and an understanding of the influence of intrinsic and extrinsic factors are limited.


Assuntos
Análise Química do Sangue/veterinária , Boidae/sangue , Testes Hematológicos/veterinária , Anestesia/veterinária , Animais , Aspartato Aminotransferases/sangue , Proteínas Sanguíneas/análise , Creatina Quinase/sangue , Contagem de Eritrócitos/veterinária , Feminino , Contagem de Leucócitos/veterinária , Masculino , Valores de Referência , Estações do Ano , Ácido Úrico/sangue
18.
Biochem J ; 440(2): 251-62, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21834793

RESUMO

Cytotoxic and antitumour factors have been documented in the venom of snakes, although little information is available on the identification of cytotoxic products in snake serum. In the present study, we purified and characterized a new cytotoxic factor from serum of the non-venomous African rock python (Python sebae), endowed with antitumour activity. PSS (P. sebae serum) exerted a cytotoxic activity and reduced dose-dependently the viability of several different tumour cell lines. In a model of human squamous cell carcinoma xenograft (A431), subcutaneous injection of PSS in proximity of the tumour mass reduced the tumour volume by 20%. Fractionation of PSS by ion-exchange chromatography yielded an active protein fraction, F5, which significantly reduced tumour cell viability in vitro and, strikingly, tumour growth in vivo. F5 is composed of P1 (peak 1) and P2 subunits interacting in a 1:1 stoichiometric ratio to form a heterotetramer in equilibrium with a hexameric form, which retained biological activity only when assembled. The two peptides share sequence similarity with PIP {PLI-γ [type-γ PLA(2) (phospholipase A(2)) inhibitor] from Python reticulatus}, existing as a homohexamer. More importantly, although PIP inhibits the hydrolytic activity of PLA(2), the anti-PLA(2) function of F5 is negligible. Using high-resolution MS, we covered 87 and 97% of the sequences of P1 and P2 respectively. In conclusion, in the present study we have identified and thoroughly characterized a novel protein displaying high sequence similarity to PLI-γ and possessing remarkable cytotoxic and antitumour effects that can be exploited for potential pharmacological applications.


Assuntos
Antineoplásicos/isolamento & purificação , Inibidores Enzimáticos/sangue , Fosfolipases A2 do Grupo IV/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Antineoplásicos/sangue , Apoptose/efeitos dos fármacos , Boidae/sangue , Neoplasias da Mama/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Feminino , Glioblastoma/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Dados de Sequência Molecular , Fosfolipases A/antagonistas & inibidores , Proteínas/isolamento & purificação , Proteínas/farmacologia , Alinhamento de Sequência
19.
Braz J Biol ; 71(2): 517-20, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21755171

RESUMO

Similarly to other reptiles, snakes are ectothermic animals and depend exclusively on the environment for the maintenance of their physiological, biochemical and immunological processes. Thus, changes in biochemical values can be expected due to seasonal influence. Twenty-two adult specimens of Boa constrictor amarali kept in captivity were used. Blood collections were done in two different seasons: winter (July 2004) and summer (January 2005) for the following assays: uric acid, aspartate aminotransferase (AST), glucose, cholesterol, total protein, and serum protein electrophoresis. The mean biochemical results found in summer and winter, respectively, were: 6.3 ± 3.4 and 11.3 ± 6.2 mg/dL for uric acid; 28.7 ± 12.4 and 20.7 ± 16.2 UI/L for AST; 26.3 ± 17 and 17.4 ± 6.8 mg/dL for glucose; 67.3 ± 30.2 and 69.7 ± 38.5 mg/dL for cholesterol; and 5.9 ± 1.6 and 5.9 ± 1.4 g/dL for total protein. Results regarding electrophoresis in summer and winter, respectively, were: 1.9 ± 0.7 and 2.4 ± 0.6 g/dL for albumin; 0.7 ± 0.2 and 0.5 ± 0.2 g/dL for α-globulin; 1.5 ± 0.5 and 1.7 ± 0.6 g/dL for ß-globulin; and 1.8 ± 0.5 and 1.5 ± 0.5 g/dL for γ-globulin. In the summer, there was a significant increase in AST and a decrease in uric acid (p < 0.05). Serum protein electrophoresis showed a significant increase in α-globulin fraction (p < 0.05) in the same season. There were not significant differences between seasons for the remaining variables. Based on these results, the period of the year must be considered in the interpretation of some biochemical values for these animals.


Assuntos
Aspartato Aminotransferases/sangue , Proteínas Sanguíneas/análise , Boidae/sangue , Colesterol/sangue , Glucose/análise , Estações do Ano , Ácido Úrico/sangue , Animais , Eletroforese , Feminino , Masculino , Proteínas/análise , Valores de Referência
20.
Braz. j. biol ; 71(2): 517-520, maio 2011. tab
Artigo em Inglês | LILACS | ID: lil-592589

RESUMO

Similarly to other reptiles, snakes are ectothermic animals and depend exclusively on the environment for the maintenance of their physiological, biochemical and immunological processes. Thus, changes in biochemical values can be expected due to seasonal influence. Twenty-two adult specimens of Boa constrictor amarali kept in captivity were used. Blood collections were done in two different seasons: winter (July 2004) and summer (January 2005) for the following assays: uric acid, aspartate aminotransferase (AST), glucose, cholesterol, total protein, and serum protein electrophoresis. The mean biochemical results found in summer and winter, respectively, were: 6.3 ± 3.4 and 11.3 ± 6.2 mg/dL for uric acid; 28.7 ± 12.4 and 20.7 ± 16.2 UI/L for AST; 26.3 ± 17 and 17.4 ± 6.8 mg/dL for glucose; 67.3 ± 30.2 and 69.7 ± 38.5 mg/dL for cholesterol; and 5.9 ± 1.6 and 5.9 ± 1.4 g/dL for total protein. Results regarding electrophoresis in summer and winter, respectively, were: 1.9 ± 0.7 and 2.4 ± 0.6 g/dL for albumin; 0.7 ± 0.2 and 0.5 ± 0.2 g/dL for α-globulin; 1.5 ± 0.5 and 1.7 ± 0.6 g/dL for β-globulin; and 1.8 ± 0.5 and 1.5 ± 0.5 g/dL for g-globulin. In the summer, there was a significant increase in AST and a decrease in uric acid (p < 0.05). Serum protein electrophoresis showed a significant increase in α-globulin fraction (p < 0.05) in the same season. There were not significant differences between seasons for the remaining variables. Based on these results, the period of the year must be considered in the interpretation of some biochemical values for these animals.


As serpentes, como outros répteis, são animais ectotérmicos e dependem exclusivamente do meio para a manutenção de seus processos fisiológicos, bioquímicos e imunológicos. Desta forma, alterações nos valores bioquímicos podem ser esperadas considerando-se a influência sazonal. Foram utilizadas vinte e duas Boa constrictor amarali adultas mantidas em cativeiro. A coleta de sangue foi realizada em duas estações diferentes: inverno (julho 2004) e verão (Janeiro 2005), para a realização dos exames: ácido úrico, aspartato aminotransferase (AST), glicose, colesterol, proteína total e eletroforese da proteína sérica. As médias dos exames bioquímicos obtidos no verão e inverno, respectivamente, foram: 6.3 ± 3.4 e 11.3 ± 6.2 mg/dL para ácido úrico; 28.7 ± 12.4 e 20.7 ± 16.2 UI/L para AST; 26.3 ± 17 e 17.4 ± 6.8 mg/dL para glicose; 67.3 ± 30.2 e 69.7 ± 38.5 mg/dL para colesterol; e 5.9 ± 1.6 e 5.9 ± 1.4 g/dL para proteína total. Os resultados da eletroforese no verão e inverno, respectivamente, foram: 1.9 ± 0.7 e 2.4 ± 0.6 g/dL para albumina; 0.7 ± 0.2 e 0.5 ± 0.2 g/dL para α globulina; 1.5 ± 0.5 e 1.7 ± 0.6 g/dL β globulina; e 1.8 ± 0.5 e 1.5 ± 0.5 g/dL para g globulina. No verão foi observado aumento significativo da AST (p < 0,05) e diminuição significativa do ácido úrico (p < 0,05). Na eletroforese de proteína sérica, houve um aumento significativo da fração a globulina (p < 0,05) na mesma estação. Para as outras variáveis não foram obtidas diferenças significativas entre as estações. De acordo com os resultados, é importante considerar o período do ano na interpretação de alguns exames bioquímicos desses animais.


Assuntos
Animais , Feminino , Masculino , Aspartato Aminotransferases/sangue , Proteínas Sanguíneas/análise , Boidae/sangue , Colesterol/sangue , Glucose/análise , Estações do Ano , Ácido Úrico/sangue , Eletroforese , Proteínas/análise , Valores de Referência
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