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Alessandra Linardi,
Thomaz A A Rocha e Silva,
Elen H Miyabara,
Carla F Franco-Penteado, Kiara C Cardoso,
Patrícia A Boer,
Anselmo S Moriscot,
José A R Gontijo,
Paulo P Joazeiro,
Carla B Collares-Buzato,
Stephen Hyslop
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ABSTRACT: Acute renal failure is a serious complication of human envenoming by Bothrops snakes. The ion pump Na+/K+-ATPase has an important role in renal tubule function, where it modulates sodium reabsorption and homeostasis of the extracellular compartment. Here, we investigated the morphological and functional renal alterations and changes in Na+/K+-ATPase expression and activity in rats injected with Bothrops alternatus snake venom.
Male Wistar rats were injected with venom (0.8 mg/kg, i.v.) and renal function was assessed 6, 24, 48 and 72 h and 7 days post-venom. The rats were then killed and renal Na+/K+-ATPase activity was assayed based on phosphate release from ATP; gene and protein expressions were assessed by real time PCR and immunofluorescence microscopy, respectively.
Venom caused lobulation of the capillary tufts, dilation of Bowman's capsular space, F-actin disruption in Bowman's capsule and renal tubule brush border, and deposition of collagen around glomeruli and proximal tubules that persisted seven days after envenoming. Enhanced sodium and potassium excretion, reduced proximal sodium reabsorption, and proteinuria were observed 6 h post-venom, followed by a transient decrease in the glomerular filtration rate. Gene and protein expressions of the Na+/K+-ATPase α1 subunit were increased 6h post-venom, whereas Na+/K+-ATPase activity increased 6 h and 24 h post-venom.
Bothrops alternatus venom caused marked morphological and functional renal alterations with enhanced Na+/K+-ATPase expression and activity in the early phase of renal damage.
Enhanced Na+/K+-ATPase activity in the early hours after envenoming may attenuate the renal dysfunction associated with venom-induced damage.
Biochimica et Biophysica Acta 06/2011; 1810(9):895-906. · 4.66 Impact Factor
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ABSTRACT: The genus Bothrops is widespread throughout Central and South America and is the principal cause of snakebite in these regions. Transcriptomic and proteomic studies have examined the venom composition of several species in this genus, but many others remain to be studied. In this work, we used a transcriptomic approach to examine the venom gland genes of Bothrops alternatus, a clinically important species found in southeastern and southern Brazil, Uruguay, northern Argentina and eastern Paraguay.
A cDNA library of 5,350 expressed sequence tags (ESTs) was produced and assembled into 838 contigs and 4512 singletons. BLAST searches of relevant databases showed 30% hits and 70% no-hits, with toxin-related transcripts accounting for 23% and 78% of the total transcripts and hits, respectively. Gene ontology analysis identified non-toxin genes related to general metabolism, transcription and translation, processing and sorting, (polypeptide) degradation, structural functions and cell regulation. The major groups of toxin transcripts identified were metalloproteinases (81%), bradykinin-potentiating peptides/C-type natriuretic peptides (8.8%), phospholipases A2 (5.6%), serine proteinases (1.9%) and C-type lectins (1.5%). Metalloproteinases were almost exclusively type PIII proteins, with few type PII and no type PI proteins. Phospholipases A2 were essentially acidic; no basic PLA2 were detected. Minor toxin transcripts were related to L-amino acid oxidase, cysteine-rich secretory proteins, dipeptidylpeptidase IV, hyaluronidase, three-finger toxins and ohanin. Two non-toxic proteins, thioredoxin and double-specificity phosphatase Dusp6, showed high sequence identity to similar proteins from other snakes. In addition to the above features, single-nucleotide polymorphisms, microsatellites, transposable elements and inverted repeats that could contribute to toxin diversity were observed.
Bothrops alternatus venom gland contains the major toxin classes described for other Bothrops venoms based on trancriptomic and proteomic studies. The predominance of type PIII metalloproteinases agrees with the well-known hemorrhagic activity of this venom, whereas the lower content of serine proteases and C-type lectins could contribute to less marked coagulopathy following envenoming by this species. The lack of basic PLA2 agrees with the lower myotoxicity of this venom compared to other Bothrops species with these toxins. Together, these results contribute to our understanding of the physiopathology of envenoming by this species.
BMC Genomics 10/2010; 11:605. · 4.07 Impact Factor
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ABSTRACT: Castor bean (Ricinus communis L.) seeds serve as raw material for the production of nonedible oil used in medicine and industry, whereas the presence of allergenic and toxic proteins in the residue left after oil extraction precludes the use of this protein-rich by-product in animal feeding. To better understand the enzymes involved in the biosynthesis and degradation of fatty acids and to identify proteins with toxic/anti-nutritional properties, extracts of developing and germinating seeds were prepared and prefractionated according to solubility properties of the proteins. An enriched plastid organelle fraction embracing mostly plastids and mitochondria was also prepared. Two-dimensional electrophoresis (2DE) reference maps of these fractions were obtained from which nearly 400 proteins were identified by matrix-assisted laser desorption ionization-time of flight-time of flight (MALDI-TOF-TOF) mass spectrometry after a search in a National Center for Biotechnology Information (NCBI) database and in an expressed sequence tag (EST) primary bank prepared from a cDNA library of developing seeds. These proteomics techniques resulted in the identification of several classes of seed reserve proteins such as 2S albumins, legumin-like and seed storage proteins, as well as other proteins of plastidial or mitochondrial functions and proteins involved in plant defense against biotic and abiotic stresses. It is expected that the collected data will facilitate the application of genetic techniques to improve the quality/profile of castor seed fatty acids, and pave the way for a rational approach to inactivate allergenic and toxic proteins, allowing the use of castor bean meal in animal feeding.
Pure and Applied Chemistry 01/2010; Pure Appl. Chem.(No. 1):259-267. · 2.79 Impact Factor
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Gustavo G L Costa, Kiara C Cardoso,
Luís E V Del Bem,
Aline C Lima,
Muciana A S Cunha,
Luciana de Campos-Leite,
Renato Vicentini,
Fábio Papes,
Raquel C Moreira,
José A Yunes,
Francisco A P Campos,
Márcio J Da Silva
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ABSTRACT: To date, oil-rich plants are the main source of biodiesel products. Because concerns have been voiced about the impact of oil-crop cultivation on the price of food commodities, the interest in oil plants not used for food production and amenable to cultivation on non-agricultural land has soared. As a non-food, drought-resistant and oil-rich crop, Jatropha curcas L. fulfils many of the requirements for biofuel production.
We have generated 13,249 expressed sequence tags (ESTs) from developing and germinating Jatropha seeds. This strategy allowed us to detect most known genes related to lipid synthesis and degradation. We have also identified ESTs coding for proteins that may be involved in the toxicity of Jatropha seeds. Another unexpected finding is the high number of ESTs containing transposable element-related sequences in the developing seed library (800) when contrasted with those found in the germinating seed library (80).
The sequences generated in this work represent a considerable increase in the number of sequences deposited in public databases. These results can be used to produce genetically improved varieties of Jatropha with increased oil yields, different oil compositions and better agronomic characteristics.
BMC Genomics 01/2010; 11:462. · 4.07 Impact Factor
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Alessandra Linardi,
Thomaz A.A. Rocha e Silva,
Elen H. Miyabara,
Carla F. Franco-Penteado, Kiara C. Cardoso,
Patrícia A. Boer,
Anselmo S. Moriscot,
José A.R. Gontijo,
Paulo P. Joazeiro,
Carla B. Collares-Buzato,
Stephen Hyslop
[show abstract]
[hide abstract]
ABSTRACT: Background
Acute renal failure is a serious complication of human envenoming by Bothrops snakes. The ion pump Na+/K+-ATPase has an important role in renal tubule function, where it modulates sodium reabsorption and homeostasis of the extracellular compartment. Here, we investigated the morphological and functional renal alterations and changes in Na+/K+-ATPase expression and activity in rats injected with Bothrops alternatus snake venom.Methods
Male Wistar rats were injected with venom (0.8 mg/kg, i.v.) and renal function was assessed 6, 24, 48 and 72 h and 7 days post-venom. The rats were then killed and renal Na+/K+-ATPase activity was assayed based on phosphate release from ATP; gene and protein expressions were assessed by real time PCR and immunofluorescence microscopy, respectively.ResultsVenom caused lobulation of the capillary tufts, dilation of Bowman's capsular space, F-actin disruption in Bowman's capsule and renal tubule brush border, and deposition of collagen around glomeruli and proximal tubules that persisted seven days after envenoming. Enhanced sodium and potassium excretion, reduced proximal sodium reabsorption, and proteinuria were observed 6 h post-venom, followed by a transient decrease in the glomerular filtration rate. Gene and protein expressions of the Na+/K+-ATPase α1 subunit were increased 6 h post-venom, whereas Na+/K+-ATPase activity increased 6 h and 24 h post-venom.Conclusions
Bothrops alternatus venom caused marked morphological and functional renal alterations with enhanced Na+/K+-ATPase expression and activity in the early phase of renal damage.General significanceEnhanced Na+/K+-ATPase activity in the early hours after envenoming may attenuate the renal dysfunction associated with venom-induced damage.Highlights► Bothrops alternatus snake venom causes renal dysfunction in rats. ► This dysfunction is accompanied by marked renal structural alterations. ► Na+/K+-ATPase expression and activity are enhanced during early renal damage. ► Enhanced Na+/K+-ATPase activity may attenuate renal dysfunction after envenoming.
Biochimica et Biophysica Acta (BBA) - General Subjects 1810(9):895-906. · 5.00 Impact Factor
