Cytotoxic activity of Androctonus australis hector venom and its toxic fractions on human lung cancer cell line

Background: Several studies have showed that animal venoms are a source of bioactive compounds that may inhibit the growth of cancer cells, which makes them useful agents for therapeutic applications. Recently, it was established that venom toxins from scorpions induced cytotoxic, antiproliferative and apoptogenic effects on cancer cells. Therefore, the present study aims to investigate the cytotoxic activity of Androctonus australis hector (Aah) scorpion venom and its toxic fractions (FtoxG-50 and F3) on NCI-H358 human lung cancer cells. Methods: The cytotoxic and antiproliferative activities were estimated using MTT assay, lactate dehydrogenase release and clonogenic assays. Apoptosis was evaluated by Hoechst 33258 staining, DNA fragmentation assay and caspase-3 activity. Oxidative stress was analyzed by reactive oxygen species, nitric oxide, malondialdehyde and protein carbonyl levels along with assessment of antioxidant status. In addition, alteration of mitochondrial membrane potential was analyzed by JC1 fluorescent dye. Results: The present findings showed that F3 fraction was more cytotoxic towards NCI-H358 lung cancer cells with an IC50 of 27.05 ± 0.70 μg/mL than venom alone (396.60 ± 1.33 μg/mL) and its toxic fraction FtoxG-50 (45.86 ± 0.91 μg/mL). Nevertheless, F3 fraction was not cytotoxic at these concentrations on normal human lung fibroblast MRC-5 cells. Inhibition of NCI-H358 cell proliferation after F3 fraction exposure occurred mainly by apoptosis as evidenced by damaged nuclei, significant DNA fragmentation level and caspase-3 activation in a dose dependent manner. Moreover, F3 fraction enhanced oxidative and nitrosative stress biomarkers and dissipated mitochondrial membrane potential in lung cancer cells along with significant depletion in cellular enzymatic and non-enzymatic antioxidants. Further, the apoptosis induced by F3 fraction was markedly prevented by the antioxidant N-acetylcysteine (NAC) suggesting the potential mechanism of oxidative stress. Conclusion: These findings suggest that F3 fraction could induce apoptosis in lung cancer cells through involvement of oxidative stress and mitochondrial dysfunction. Hence, these properties make F3 fraction a promising candidate for development of new anticancer agents.(AU)

A study on the genetic diversity of Androctonus crassicauda (Olivier, 1807; Scorpiones: Buthidae) from Turkey

Mitochondrial DNA (mtDNA) has been widely employed in phylogeographic and phylogenetic studies. In the present study, the genetic identification of the scorpion Androctonus crassicauda (Olivier, 1807) was carried out by using the 16S mitochondrial gene, since this scorpion represents the most important species in Turkey regarding scorpionism and antivenom production. Two genetic groups were found according to the sequence analysis results, while five different loci at the nucleotide level presented genetic variation in the 16S region when compared to a known A. crassicauda sequence data (GenBank, AJ277598). Nucleotide variations found in the current work constitute the first descriptive report for A. crassicauda. Moreover, future studies may enlighten the genetic and venom composition variations for this scorpion species.(AU)

New additions to the scorpion fauna of Riyadh region, Saudi Arabia

In this work, we present additional morphological data about the scorpion fauna of Saudi Arabia. This investigation was carried out in the central region (Riyadh) of the country and identified existing and newly discovered scorpion species for taxonomic documentation while determining the medically important ones. The survey covered the entire Riyadh region, including all major districts, and collected a total of 4,164 specimens. Morphological identification of collected animals was based on identification keys. There were two species (one with a subspecies) that belonged to the family Scorpionidae, namely Scorpio maurus kruglovi (0.02 percent) and Hemiscorpius arabicus (0.05 percent). The latter, currently, is part of the Hemiscorpiidae family that had been upgraded from a subfamily. Eight more species from the Buthidae family were found: Leiurus quinquestriatus (7.20 percent), Androctonus crassicauda (17.24 percent), Androctonus bicolor (64.60 percent), Compsobuthus arabicus (3.84 percent), Compsobuthus werneri (0.94 percent), Buthacusyotvatensis nigroaculeatus (2.31 percent), Buthacusleptochelys (3.24 percent) and Orthochirus innesi (0.55 percent). The major locations of collection were the outskirts of Riyadh city and the airport vicinity. The specimens were transported from all central region areas in 124 short trips.(AU)

Evaluation of the neutralizing capacity of Androctonus crassicauda (Olivier, 1807) antivenom against Leiurus quinquestriatus (Ehrenberg, 1928) venom (Scorpiones: Buthidae)

The two most venomous species of the family Buthidae, Leiurus quinquestriatus and Androctonus crassicauda, are found in Africa and in the Middle East. Potency and paraspecific activities of A. crassicauda antivenom (RSHC anti-Ac) were tested against L. quinquestriatus venom. The sera produced by Refik Saydam Hygiene Center (RSHC) showed strong reactivity against the venoms of A. crassicauda and L. quinquestriatus in western blotting and dot-blot analysis. RSHC anti-Ac presents immunoactivity and neutralizing potential against Leiurus quinquestriatus venom. Neutralization capacity of antivenom was found to be 400 µL against 40 minimum lethal doses (MLD) of A. crassicauda scorpion venom and 10 MLD of L. quinquestriatus venom. This study indicates that the RSHC anti-Ac could be used for treating L. quinquestriatus stings.(AU)

Effects of Androctonus crassicauda (Olivier, 1807) (Scorpiones: Buthidae) venom on rat metabolism

Scorpions are venomous arthropods of the Arachnida class and are considered relatives of spiders, ticks and mites. There is not any study about the biochemical effects of Androctonus crassicauda (Olivier, 1807) venom. Therefore, in the present study, we aimed at evaluating the toxicity of the venom from A. crassicauda, which is responsible for a number of deaths of infants, children and adults in tropical and subtropical countries. For this purpose, rats (n=35) were divided into seven groups of five animals each; venom solutions (250µg/kg) were subcutaneously injected into rats; blood samples were taken from each animal at various times; and serum biochemical parameters were measured (levels of total proteins, total bilirubin, albumin, globulin, urea, creatinine, uric acid, glucose, cholesterol, triglycerides, sodium, chlorine, potassium and calcium, and the activity of the enzymes alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, lactate dehydrogenase). Serum levels of glucose, cholesterol, aspartate aminotransferase, alanine aminotransferase and uric acid increased in envenomed animals, compared to controls. There was a statistically positive correlation between Na+ and Cl- ions.(AU)

Determination of potency and paraspecific effects of Androctonus crassicauda (Olivier, 1807) antivenom against Mesobuthus gibbosus (Brullé, 1832) venom (Scorpiones: Buthidae)

Scorpion envenomation remains a real health problem in many countries. In scorpionism cases, it is often recommended that patients be treated with species-specific antivenom. Androctonus crassicauda venom has been used as antigen for antivenom production in Turkey, where this antivenom, called Turkish antivenom, has also been effective in the treatment of envenomation caused by species other than A. crassicauda. The present study aimed at determining the paraspecific effects and potency of the Turkish antivenom against Mesobuthus gibbosus (Brullé, 1832) venom. To assess the venom toxicity and the antivenom efficacy, we determined the Minimum Lethal Dose (MLD) and the Minimum Effective Dose (MED) instead of LD50 and ED50, respectively. Androctonus crassicauda antivenom was capable of neutralizing M. gibbosus venom (20 MLD). This was the first study indicating that A. crassicauda antivenom can be used for the treatment of Mesobuthus gibbosus stings, especially in Aegean Region, Turkey.(AU)

Effects of Androctonus crassicauda (Olivier, 1807) (scorpiones: buthidae) venom on rats: correlation among acetylcholinesterase activities and electrolytes levels

Scorpions can be considered living fossils because they have changed so little during the last 400 million years. They are venomous arthropods of the Arachnida class and regarded as relatives of spiders, ticks and mites. The aim of the present study was to evaluate the toxicity of Androctonus crassicauda (Olivier, 1807) venom and its effects on the acetylcholinesterase (AchE) activity and on electrolytes levels in rats. Animals were divided into seven groups of five rats each. Test groups received 250æg/kg of venom solution while control group was treated with 200æl of physiological saline solution (PSS). Blood samples were collected from the animals on the 1st, 2nd 4th, 8th, 12th, and 24th hours after subcutaneous injection of venom. Animals were monitored for 24 hours. Androctonus crassicauda venom significantly reduced AchE activity on the 12th hour when compared with control group. A statistically negative correlation between Na+ and K+ (p<0.05) and a positive correlation between Na+ and CL- (p<0.001) ions levels were observed after the administration of A. crassiccauda venom to rats. We can conclude that the differences in the electrolytes levels are due to acute renal failure, since elimination of toxin occurs primarily via the kidney.(AU)

Parametric values of Androctonus crassicauda (Oliver, 1807) (scorpiones: buthidae) from Turkey

The aim of the present study was to analyze the parametric values of Androctonus crassicauda (Oliver, 1807), the most significant scorpion species in Turkey. For this purpose, 11 male and 11 female A. crassicauda specimens were collected from Sanliurfa region. The body parts most important for species identification were measured by using sensitive calipers. Differences between sexes were statistically significant for pectinal organ length (female: 7.50±1.26mm;male: 8.63±1.05mm; p=0.033), pectinal tooth count (female: 25.36±0.86;male: 33.36±0.80; p=0.000), and carapace width (female: 10.27±1.19mm;male: 9.09±0.73mm; p=0.000). However, body length (female: 90.09±14.74mm;male: 82.95±5.40mm), abdomen width (female: 12.09±1.90mm;male: 11.09±0.88mm), and metasoma length (female: 43.09±3.08mm;male: 44.63±6.50mm) were not significantly different between sexes.(AU)