Centruroides tecomanus is a Mexican scorpion endemic of the State of Colima, that causes human fatalities. This communication describes a proteome analysis obtained from milked venom and a transcriptome analysis from a cDNA library constructed from two pairs of venom glands of this scorpion. High perfomance liquid chromatography separation of soluble venom produced 80 fractions, from which at least 104 individual components were identified by mass spectrometry analysis, showing to contain molecular masses from 259 to 44,392 Da. Most of these components are within the expected molecular masses for Na+- and K+-channel specific toxic peptides, supporting the clinical findings of intoxication, when humans are stung by this scorpion. From the cDNA library 162 clones were randomly chosen, from which 130 sequences of good quality were identified and were clustered in 28 contigs containing, each, two or more expressed sequence tags (EST) and 49 singlets with only one EST. Deduced amino acid sequence analysis from 53% of the total ESTs showed that 81% (24 sequences) are similar to known toxic peptides that affect Na+-channel activity, and 19% (7 unique sequences) are similar to K+-channel especific toxins. Out of the 31 sequences, at least 8 peptides were confirmed by direct Edman degradation, using components isolated directly from the venom. The remaining 19%, 4%, 4%, 15% and 5% of the ESTs correspond respectively to proteins involved in cellular processes, antimicrobial peptides, venom components, proteins without defined function and sequences without similarity in databases. Among the cloned genes are those similar to metalloproteinases.
Scorpions belonging to the Buthidae family have traditionally drawn much of the biochemist’s attention due to the strong toxicity of their venoms. Scorpions not toxic to mammals, however, also have complex venoms. They have been shown to be an important source of bioactive peptides, some of them identified as potential drug candidates for the treatment of several emerging diseases and conditions. It is therefore important to characterize the large diversity of components found in the non-Buthidae venoms. As a contribution to this goal, this manuscript reports the construction and characterization of cDNA libraries from four scorpion species belonging to the Vaejovis genus of the Vaejovidae family: Vaejovis mexicanus, V. intrepidus, V. subcristatus and V. punctatus. Some sequences coding for channel-acting toxins were found, as expected, but the main transcribed genes in the glands actively producing venom were those coding for non disulfide-bridged peptides. The ESTs coding for putative channel-acting toxins, corresponded to sodium channel β toxins, to members of the potassium channel-acting α or κ families, and to calcium channel-acting toxins of the calcin family. Transcripts for scorpine-like peptides of two different lengths were found, with some of the species coding for the two kinds. One sequence coding for La1-like peptides, of yet unknown function, was found for each species. Finally, the most abundant transcripts corresponded to peptides belonging to the long chain multifunctional NDBP-2 family and to the short antimicrobials of the NDBP-4 family. This apparent venom composition is in correspondence with the data obtained to date for other non-Buthidae species. Our study constitutes the first approach to the characterization of the venom gland transcriptome for scorpion species belonging to the Vaejovidae family.
1 July 2004 in Blood Cells, Molecules, and Diseases
Uterine cervical cancer (UCC) is one of the main causes of cancer‑associated mortality in women. Inflammation has been identified as an important component of this neoplasia; in this context, anti‑inflammatory drugs represent possible prophylactic and/or therapeutic alternatives that require further investigation. Anti‑inflammatory drugs are common and each one may exhibit a different antineoplastic effect. As a result, the present study investigated different anti‑inflammatory models of UCC in vitro and in vivo. Celecoxib, sulindac, nimesulide, dexamethasone, meclofenamic acid, flufenamic acid and mefenamic acid were tested in UCC HeLa, VIPA, INBL and SiHa cell lines. The cytotoxicity of the drugs was evaluated in vitro. Celecoxib, sulindac, nimesulide, mefenamic acid and flufenamic acid presented with slight to moderate toxicity (10‑40% of cell death corresponding to 100 µM) in certain cell lines, while meclofenamic acid exhibited significant cytotoxicity in all essayed cell lines (50‑90% of cell death corresponding to 100 µM). The meclofenamic acid was tested in murine models (immunodeficient and immunocompetent) of UCC, which manifested a significant reduction in tumor growth and increased mouse survival. It was demonstrated that of the evaluated anti‑inflammatory drugs, meclofenamic acid was the most cytotoxic, with a significant antitumor effect in murine models. Subsequent studies are necessary to evaluate the clinical utility of this drug.