A transcriptomic analysis of gene expression in the venom gland of the snake Bothrops alternatus (urutu)

<p>Abstract</p> <p>Background</p> <p>The genus <it>Bothrops </it>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 <it>Bothrops alternatus</it>, a clinically important species found in southeastern and southern Brazil, Uruguay, northern Argentina and eastern Paraguay.</p> <p>Results</p> <p>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 A₂were essentially acidic; no basic PLA₂were 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.</p> <p>Conclusions</p> <p><it>Bothrops alternatus </it>venom gland contains the major toxin classes described for other <it>Bothrops </it>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 PLA₂agrees with the lower myotoxicity of this venom compared to other <it>Bothrops </it>species with these toxins. Together, these results contribute to our understanding of the physiopathology of envenoming by this species.</p

Byrsonima intermedia A. Juss partitions promote gastroprotection against peptic ulcers and improve healing through antioxidant and antiinflammatory activities.

Byrsonima intermedia is a species of bush popularly used to treat gastrointestinal disorders, such as gastric ulcers, gastritis, and diarrhea. Previous studies have revealed that the methanolic crude extract of B. intermedia leaves has gastroprotective and healing properties. In this new study, we specifically investigated two purified partitions, ethyl acetate (EtOAc) and water (AcoAq), obtained from the crude extract to characterize the antiulcer effects of these two partitions and the mechanisms of action of this medicinal plant. The healing effects of these partitions on the gastric and duodenal mucosa were assessed after ischemia-reperfusion (I/R) or acetic acidinduced injury. The involvement of tumor necrosis factor-alpha (TNF-alpha), interleukin 1&#946; (IL-1&#946;), interleukin 10 (IL-10), and myeloperoxidase (MPO) activity and glutathione (GSH) levels were determined. The antibacterial activity against Helicobacter pylori was evaluated using microdilution methods. The phytochemical analysis of AcoAq revealed a predominance of oligomeric proanthocyanidins and galloyl quinic esters, whereas EtOAc was found to contain concentrated flavonoids. Both partitions led to a significant reduction in gastric lesions, but AcoAq was more effective than EtOAc with regard to anti-Helicobacter pylori activity in addition to protecting the gastric mucosa against ethanol, non-steroidal anti-inflammatory drugs (NSAIDs) and duodenal mucosal damage induced by cysteamine. Additionally, both partitions were associated with a significant increase in gastric and duodenal healing and increased gastric mucosal GSH content after damage induced by acetic acid. On the other hand, after 6 days of treatment, EtOAc was more effective than AcoAq in ameliorating gastric damage upon initiation of the gastric I/R, which was accompanied by a significant reduction in the activity of gastric mucosal MPO, IL 1-&#946; and TNFalpha, as well as an elevation in IL-10 and GSH content. These results demonstrate that the oligomeric proanthocyanidins and galloyl quinic esters present in AcoAq were more effective in the prevention of gastric and duodenal ulcers due to the antioxidant effects of these compounds, whereas the flavonoids present in EtOAc were more effective due to their anti-inflammatory activity on the gastric and duodenal tissue. All these results confirm that the rich phytochemical diversity of B. intermedia contributes to the pharmacological actions of this medicinal plant on the gastrointestinal tract in addition to its activity against H. pylori

Aneurisma dissecante de artéria vertebral intracraniana fenestrada submetido ao tratamento endovascular: relato de caso Dissecting: aneurysm of the intracranial fenestrated vertebral artery submited to endovascular treatment case report

Aneurismas dissecantes da artéria vertebral em seu segmento intracraniano são lesões pouco comuns, principalmente quando associadas a hemorragia subaracnóidea, sendo também raras as fenestrações da artéria vertebral. Apresentam elevada morbidade e mortalidade, com elevado índice de ressangramento e dificuldade de abordagem cirúrgica. Apresentamos o caso de um homem de 19 anos, o qual foi vitima de agressão física em região occipto-cervical, apresentando hemorragia subaracnóidea e aneurisma dissecante na artéria vertebral direita, a qual era fenestrada, sendo submetido ao tratamento endovascular. Realizamos revisão da literatura sobre o assunto, sendo colocado o tratamento endovascular como uma opção terapêutica para estes casos.<br>Dissecting aneurysms of the vertebral artery at its intracranial segment are uncommon lesions, mainly when associated to subarachnoid hemorrhage, being also rare fenestrations of the vertebral artery. They present high morbidity and mortality, with high rebleeding rate and difficulty of surgical approach. We present a 19 years old man who was victim of physical aggression in the occipto-cervical region, presenting subarachnoid hemorrhage and a dissecting aneurysm of the right vertebral artery, which had a fenestration, being submitted to endovascular treatment. We accomplished a literature review about this subject, proposing endovascular treatment as a therapeutic option for these cases