Venomous Species Research Articles

Analysis and prediction of animal toxins by various Chou's pseudo components and reduced amino acid compositions

The animal toxin proteins are one of the disulfide rich small peptides that detected in venomous species. They are used as pharmacological tools and therapeutic agents in medicine for the high specificity of their targets. The successful analysis and prediction of toxin proteins may have important signification for the pharmacological and therapeutic researches of toxins. In this study, significant differences were found between the toxins and the non-toxins in amino acid compositions and several important biological properties. The random forest was firstly proposed to predict the animal toxin proteins by selecting 400 pseudo amino acid compositions and the dipeptide compositions of reduced amino acid alphabet as the input parameters. Based on dipeptide composition of reduced amino acid alphabet with 13 reduced amino acids, the best overall accuracy of 85.71% was obtained. These results indicated that our algorithm was an efficient tool for the animal toxin prediction.

Venom of prey-specialized spiders is more toxic to their preferred prey: A result of prey-specific toxins.

In specialized predators, a variety of adaptations have evolved to such a level of specificity that they allow very effective exploitation of focal prey. Venom is an essential adaptive trait of predatory venomous species, such as spiders, yet our knowledge of spider venom is incomplete. In agreement with the prey preference hypothesis, we expected that the venom of spider specialists should be more toxic to focal than to alternative prey, because it is composed of prey-specific toxins. Here we used spiders with three types of trophic specializations: specialists that were ant-eating, termite-eating and spider-eating. We compared the efficacy of prey capture of preferred and alternative prey (measured as paralysis latency) with that of related generalists and profiled the venom of the studied species using proteomic methods. We used 22 spider species: six myrmecophagous, two termitophagous, three araneophagous and 11 euryphagous generalist species belonging to different families. We found that ten of the eleven specialist species induced significantly shorter paralysis latency in preferred prey than in alternative prey. Generalists exhibited either similar efficiency on both prey types or slightly higher efficiency on preferred prey. Multivariate analysis of proteomic profiles (peptides and proteins) revealed significant differences between trophic specializations, particularly in peptides. Specialists appear to have venom composed of unique specific compounds as revealed by the multivariate ordination and indicator analysis. These components are likely prey-specific toxins.

Venom Protein C Activators as Diagnostic Agents for Defects of Protein C System.

Protein C is a vitamin K dependent plasma zymogen. It inhibits clotting by inhibiting clotting by inactivating factor V and factor VIII. Protein C activation pathway involves three steps: (i) Activation of protein C; (ii) Inhibition of coagulation through inactivating factor V and VIII by activated protein C and (iii) Inhibition of activated protein C by plasma protease inhibitors specific for this enzyme. Proteinases converting the zymogen protein C (PC) of vertebrates into activated PC have been detected in several snake venoms. Most PC activators have been purified from venom of snake species belonging to the genera of the Agkistrodon complex. Unlike the physiological thrombin-catalyzed PC activation reaction which requires thrombomodulin as a cofactor, most snake venom activators directly convert the zymogen PC into the catalytically active form which can easily be determined by means of coagulation or chromogenic substrate techniques. The fast-acting PC activator Protac® from Agkistrodon contortrix contortrix (Southern copperhead snake) venom has found a broad application in diagnostic practice for the determination of disorders in the PC pathway. Recently, screening assays for the PC pathway have been introduced, based on the observation that the PC pathway is probably the most important physiological barrier against thrombosis.

Evaluating the potential for evolutionary mismatch in Batesian mimics: A case study in the endangered smooth snake (Coronella austriaca).

Many harmless organisms gain a survival advantage by mimicking venomous species. This is the case of the endangered smooth snake (Coronella austriaca), which mimics venomous vipers. Although this may protect the smooth snake against most of its natural predators, it may render them at greater risk of mortality from humans, who are more inclined to kill species, such as vipers, that they consider dangerous. This may cause an evolutionary mismatch, whereby humans may counteract the natural advantage of mimicry. We explore this possibility of evaluating the willingness of humans to kill smooth snakes versus the adder (Vipera berus), as well as their ability to discern them in the Åland Islands. Our results show that, even when respondents did not wish to kill the smooth snakes, these were often mistaken for adders, which they were willing to kill. Altogether, viper mimicry brought about a 2.3‐fold increase in the likelihood of smooth snakes being killed upon human encounter. These results open up the possibility that naturally selected mimicry can pose a threat to endangered snakes in human‐influenced habitats. We discuss the potential for this to be the case, and highlight the importance of protecting entire mimicry complexes, rather than single species, when the endangered species is a mimic.

Effects of Heme Modulation on Ovophis and Trimeresurus Venom Activity in Human Plasma

Geographic isolation and other factors result in evolution-driven diversity of the enzymatic composition of venom of pit vipers in the same genus. The present investigation sought to characterize venoms obtained from such genetically diverse Ovophis and Trimeresurus pit vipers utilizing thrombelastographic coagulation kinetic analyses. The coagulation kinetics of human plasma were assessed after exposure to venom obtained from two Ovophis and three Trimeresurus species. The potency of each venom was defined (µg/mL required to equivalently change coagulation); additionally, venoms were exposed to carbon monoxide (CO) or a metheme-inducing agent to modulate any enzyme-associated heme. All venoms had fibrinogenolytic activity, with four being CO-inhibitable. While Ovophis venoms had similar potency, one demonstrated the presence of a thrombin-like activity, whereas the other demonstrated a thrombin-generating activity. There was a 10-fold difference in potency and 10-fold different vulnerability to CO inhibition between the Trimeresurus species. Metheme formation enhanced fibrinogenolytic-like activity in both Ovophis species venoms, whereas the three Trimeresurus species venoms had fibrinogenolytic-like activity enhanced, inhibited, or not changed. This novel “venom kinetomic” approach has potential to identify clinically relevant enzymatic activity and assess efficacy of antivenoms between genetically and geographically diverse species.

Inactivation of Venom PLA₂ Alleviates Myonecrosis and Facilitates Muscle Regeneration in Envenomed Mice: A Time Course Observation.

Snake venom is a complex cocktail of toxins which induces a series of clinical and pathophysiological manifestations in victims, including severe local tissue damage and systemic alterations. Deinagkistrodon acutus (D. acutus) ranks among the “big four” life-threatening venomous species in China, whose venom possesses strong myotoxicity and hematotoxicity that often lead to permanent disability or muscle atrophy. Varespladib, an inhibitor of mammalian phospholipase A2 (PLA2), has been recently reproposed as an effective antidote against snakebite envenomation. The present study aimed at evaluating the protective role of varespladib on muscle regeneration in envenomed mice. Mice were grouped and subjected to inoculation with D. acutus venom or a mixture of venom and varespladib or control vehicle in the gastrocnemius muscle. Local injuries including hemorrhage, myonecrosis, ulceration, and systemic damages including general dysfunction, visceral failure, and inflammatory responses were observed at 1, 3, 7, 14, and 21 days. The results indicated that most of the muscle myonecrosis and hemorrhage were alleviated by varespladib. Besides, the pretreated mice recovered rapidly with lesser atrophy and muscle fibrosis. In conclusion, the findings of the present study suggested that varespladib is an effective antidote that could neutralize D. acutus venom and allow for earlier and improved rehabilitation outcome.

Anti-inflammatory properties of Centaurea calolepis Boiss. and cnicin against Macrovipera lebetina obtusa (Dwigubsky, 1832) and Montivipera xanthina (Gray, 1849) venoms in rat

Macrovipera lebetina obtusa (Dwigubsky, 1832) and Montivipera xanthina (Gray, 1849) (Ottoman Viper) are viper snakes from Viperidae family and found in various locations in Anatolia. Both snakes are responsible for major snake bite cases in Turkey Their venoms cause necrosis, hemorrhage, pain and local edema.Centaurea L. (Asteraceae) species draw attention as potential anti-inflammatory sources due to their traditional uses and accomplished studies on this field. C. calolepis Boiss. is an endemic taxon distributed in Aegean and Antalya regions in Turkey. Chloroform extract of C. calolepis and its major compound cnicin, a sesquiterpene lactone, are reported to have strong anti-inflammatory activities in-vitro, by previous studies.In the present study, in-vivo anti-inflammatory activities of C. calolepis chloroform extract and the sesquiterpenoid cnicin against edema induced by Macrovipera lebetina obtusa and Montivipera xanthina venoms were evaluated in the rat model. Protein contents and induction doses of the venoms were determined. Carrageenan and snake venoms were used as inducing agents in paw edema tests.Extract demonstrated strong inhibition on edema at all doses and hours against M. xanthina venom and carrageenan. Inhibition ratio of extract at 25 mg/kg dose (84.13% inhibition) after 0.5 h M. xanthina venom injection was more than indomethacin's value (45.4% inhibition). The extract also showed significant effect also on inflammation caused by M. lebetina obtusa venom at all doses. However, 2.5 mg/kg cnicin was more effective than total extract of C. calolepis against rat paw edema induced by (27.31%) M. lebetina obtusa venom.This is the first study reported therapeutic potential of C. calolepis, an endemic plant of Turkey, in case of snake-bites cause inflammation by venomous species in natural fauna of Anatolia.

Vulnerability to snakebite envenoming: a global mapping of hotspots

SummaryBackgroundSnakebite envenoming is a frequently overlooked cause of mortality and morbidity. Data for snake ecology and existing snakebite interventions are scarce, limiting accurate burden estimation initiatives. Low global awareness stunts new interventions, adequate health resources, and available health care. Therefore, we aimed to synthesise currently available data to identify the most vulnerable populations at risk of snakebite, and where additional data to manage this global problem are needed.MethodsWe assembled a list of snake species using WHO guidelines. Where relevant, we obtained expert opinion range (EOR) maps from WHO or the Clinical Toxinology Resources. We also obtained occurrence data for each snake species from a variety of websites, such as VertNet and iNaturalist, using the spocc R package (version 0.7.0). We removed duplicate occurrence data and categorised snakes into three groups: group A (no available EOR map or species occurrence records), group B (EOR map but <5 species occurrence records), and group C (EOR map and ≥5 species occurrence records). For group C species, we did a multivariate environmental similarity analysis using the 2008 WHO EOR maps and newly available evidence. Using these data and the EOR maps, we produced contemporary range maps for medically important venomous snake species at a 5 × 5 km resolution. We subsequently triangulated these data with three health system metrics (antivenom availability, accessibility to urban centres, and the Healthcare Access and Quality [HAQ] Index) to identify the populations most vulnerable to snakebite morbidity and mortality.FindingsWe provide a map showing the ranges of 278 snake species globally. Although about 6·85 billion people worldwide live within range of areas inhabited by snakes, about 146·70 million live within remote areas lacking quality health-care provisioning. Comparing opposite ends of the HAQ Index, 272·91 million individuals (65·25%) of the population within the lowest decile are at risk of exposure to any snake for which no effective therapy exists compared with 519·46 million individuals (27·79%) within the highest HAQ Index decile, showing a disproportionate coverage in reported antivenom availability. Antivenoms were available for 119 (43%) of 278 snake species evaluated by WHO, while globally 750·19 million (10·95%) of those living within snake ranges live more than 1 h from population centres. In total, we identify about 92·66 million people living within these vulnerable geographies, including many sub-Saharan countries, Indonesia, and other parts of southeast Asia.InterpretationIdentifying exact populations vulnerable to the most severe outcomes of snakebite envenoming at a subnational level is important for prioritising new data collection and collation, reinforcing envenoming treatment, existing health-care systems, and deploying currently available and future interventions. These maps can guide future research efforts on snakebite envenoming from both ecological and public health perspectives and better target future estimates of the burden of this neglected tropical disease.FundingBill & Melinda Gates Foundation.

Mass spectrometry-assisted venom profiling of Hypnale hypnale found in the Western Ghats of India incorporating de novo sequencing approaches

Hypnale hypnale (hump-nosed pit viper) is considered to be one among the medically important venomous snake species of India and Sri Lanka. In the present study, venom proteome profiling of a single Hypnale hypnale from Western Ghats of India was achieved using SDS-PAGE based protein separation followed by LC-MS/MS analysis. The identities of the proteins that were not established using the Mascot search were determined through de novo sequencing tools such as Novor followed by MS-BLAST based sequence similarity search algorithm and PEAKS proteomics software. The combined proteomics analysis revealed a total of 37 proteins belonging to nine different snake venom families, in which 7 proteins were exclusively identified through de novo strategies. The enzymatic and non-enzymatic venom protein families identified include serine proteases, metalloproteases, phospholipase A2, thrombin-like enzymes, phospholipase B, C-type lectins/snaclecs, disintegrins, cysteine rich secretory proteins and nerve growth factor. Among these, disintegrins, nerve growth factor, phospholipase B and cysteine rich secretory protein families were identified for the first time in HPV venom. This could possibly explain the regiospecific venom variation seen across snake species. Taken together, the venom proteome profiling on Indian Hypnale hypnale venom correlates with the clinical manifestations often seen in the envenomed victims.

Lionfish venom elicits pain predominantly through the activation of nonpeptidergic nociceptors.

The lionfish (Pterois volitans) is a venomous invasive species found in the Caribbean and Northwestern Atlantic. It poses a growing health problem because of the increase in frequency of painful stings, for which no treatment or antidote exists, and the long-term disability caused by the pain. Understanding the venom's algogenic properties can help identify better treatment for these envenomations. In this study, we provide the first characterization of the pain and inflammation caused by lionfish venom and examine the mechanisms through which it causes pain using a combination of in vivo and in vitro approaches including behavioral, physiological, calcium imaging, and electrophysiological testing. Intraplantar injections of the venom produce a significant increase in pain behavior, as well as a marked increase in mechanical sensitivity for up to 24 hours after injection. The algogenic substance(s) are heat-labile peptides that cause neurogenic inflammation at the site of injection and induction of Fos and microglia activation in the superficial layers of the dorsal horn. Finally, calcium imaging and electrophysiology experiments show that the venom acts predominantly on nonpeptidergic, TRPV1-negative, nociceptors, a subset of neurons implicated in sensing mechanical pain. These data provide the first characterization of the pain and inflammation caused by lionfish venom, as well as the first insight into its possible cellular mechanism of action.

Proteomic characterization of six Taiwanese snake venoms: Identification of species-specific proteins and development of a SISCAPA-MRM assay for cobra venom factors

Deinagkistrodon acutus, Trimeresurus stejnegeri, Protobothrops mucrosquamatus, Daboia russelii siamensis, Bungarus multicinctus and Naja atra are the six medically important venomous snake species in Taiwan. In this study, we characterized and compared their venom protein profiles using proteomic approaches. The major snake venom proteins were identified by GeLC-MS/MS and the total venom proteome was characterized by in-solution digestion coupled with LC-MS/MS. A total of 27–52 proteins, categorized into 23 protein families, were identified in each snake's venom. The major venom components found in Viperidae species (D. acutus, T. stejnegeri, P. mucrosquamatus and D. russelii) were C-type lectin, snake venom serine proteinase, venom metalloproteinase and phospholipase A2, whereas three-finger toxin and phospholipase A2 were the major components detected in the venom of Elapidae snakes (B. multicinctus and N. atra). This study also provided the first demonstration of some low-abundance proteins in these six snake venoms, including 5′-nucleotidase, glutaminyl-peptide cyclotransferase and phosphodiesterase, among others. Furthermore, we found that cobra venom factor (CVF) is a cobra-specific protein. We produced anti-peptide antibodies against CVF and used it to develop a highly sensitive SISCAPA-MRM assay for quantifying CVF. The limit of detection and lower limit of quantification were 3.2 and 9.6 attomoles, respectively. This assay was used to precisely quantify CVF in 1 μg crude venom proteins from three Naja species and king cobra. The amount of CVF varied from 0.9 to 54.36 femtomoles (equivalent to 0.16–10.03 mg/g of venom protein). Biological significanceThere are six medically significant venomous snakes in Taiwan. The venoms of the four Viperidae species (Deinagkistrodon acutus, Trimeresurus stejnegeri, Protobothrops mucrosquamatus and Daboia russelii siamensis) cause local tissue swelling; this symptom is also seen in N. atra envenomation in humans, potentially complicating the differential diagnosis of envenomation by N. atra and Viperidae species. Thus, characterization of the venom proteomes of the six Taiwanese snakes, including the relative abundance of the major components and species-specific protein(s) in each venom type, could be useful for future venom research, including the development of new assay(s) for detecting snake species-specific venom protein(s) and new type(s) of antivenom.

A novel pentameric phospholipase A2 myotoxin (PophPLA2) from the venom of the pit viper Porthidium ophryomegas

The first toxin isolated from the venomous pit viper Porthidium ophryomegas is a basic pentameric phospholipase A2 (PophPLA2). Elucidation of its amino acid sequence showed that it belongs to the group IIA of secreted PLA2s, with the presence of all 14 conserved cysteine positions. The toxin displayed catalytic activity, in agreement with the presence of Asp49 in its sequence of 121 residues. SDS-PAGE analysis revealed that this toxin is pentameric in non-reducing conditions, a structural organization that has not been described for any viperid PLA2. PophPLA2 displayed moderate myotoxic (in vivo) and cytotoxic (in vitro) activities, as well as anticoagulant activity on human plasma (in vitro). PophPLA2 was not lethal, and did not induce signs of toxicity or distress in mice, when administered intravenously at a dose of up to 100 μg (5.9 μg/g). The toxin showed highest sequence identity with other PLA2s from the venoms of ancestral Asian pit viper species.

Potential effects of climate change on the risk of accidents with poisonous species of the genus Tityus (Scorpiones, Buthidae) in Argentina

The temporal pattern of co-occurrence of human beings and venomous species (scorpions, spiders, snakes) is changing. Thus, the temporal pattern of areas with risk of accidents with such species tends to become dynamic in time. We analyze the areas of occurrence of species of Tityus in Argentina and assess the impact of global climate change on their area of distribution by the construction of risk maps. Using data of occurrence of the species and climatic variables, we constructed models of species distribution (SMDs) under current and future climatic conditions. We also created maps that allow the detection of temporal shifts in the distribution patterns of each Tityus species. Finally, we developed risk maps for the analyzed species. Our results predict that climate change will have an impact on the distribution of Tityus species which will clearly expand to more southern latitudes, with the exception of T. argentinus. T. bahiensis, widely distributed in Brazil, showed a considerable increase of its potential area (ca. 37%) with future climate change. The species T. confluens and T. trivittatus that cause the highest number of accidents in Argentina are expected to show significant changes of their distributions in future scenarios. The former fact is worrying because Buenos Aires province is the more densely populated district in Argentina thus iable to become the most affected by T. trivittatus. These alterations of distributional patterns can lead to amplify the accident risk zones of venomous species, becoming an important subject of concern for public health policies.

Identification of a hypotensive and bradycardic peptide from Black Mamba snake venom

It is estimated that there are about 170,000 venomous species throughout the world. The venom produced by their glands contains hundreds of bioactive compounds. These natural libraries open complete new therapeutic avenues. Heart failure is a cardiac disease associated with morbidities. Recent progress in medicine allowed to develop treatments, yet they are often not highly efficient and possess harmful side effects. Given that venom compounds are pharmacologically active, they can be considered as a source of life-saving therapeutics. The aim of our study is to find therapeutic effects of venom compounds to treat hypertension which can lead to heart failure. Black Mamba snake venom fractionations were performed by using cation exchange and RP-HPLC techniques. The obtained fractions and purified compounds were investigated for their ability to displace 3 H-NMS from muscarinic type 2 receptors (M2R). One particular snake peptide, found to be active, was de novo sequenced and synthesized. This peptide was studied in vivo by invasive hemodynamics to evaluate the main cardiovascular parameters ( n = 5, 100 μg/kg) and ex vivo on isolated mesenteric and aorta arteries ( n = 6; 0.8 nM, 8 nM, 80 nM and 8 μM). Wistar rats that were 10–12 weeks old were used for this study. After consecutive fractionations of the venom, we succeeded to identify a unique peptide with major hypotension effects. Once injected intravenously in vivo, invasive hemodynamic studies highlighted a significant arterial blood pressure decrease (−65%, P < 0.001) and a reduction in heart rate (−14%, P < 0.001). It also induced a relaxation of mesenteric and aorta arteries (−90%, P < 0.05 vs. baseline). Whether these effects are due to M2R, their regulation will be discussed. In this study, we demonstrated the hypotensive effect of an isolated peptide from Black Mamba snake. These results confirm that venom compounds represent a promising opportunity to develop new drugs.

Innovative assembly strategy contributes to understanding the evolution and conservation genetics of the endangered Solenodon paradoxus from the island of Hispaniola.

Solenodons are insectivores that live in Hispaniola and Cuba. They form an isolated branch in the tree of placental mammals that are highly divergent from other eulipothyplan insectivores The history, unique biology, and adaptations of these enigmatic venomous species could be illuminated by the availability of genome data. However, a whole genome assembly for solenodons has not been previously performed, partially due to the difficulty in obtaining samples from the field. Island isolation and reduced numbers have likely resulted in high homozygosity within the Hispaniolan solenodon (Solenodon paradoxus). Thus, we tested the performance of several assembly strategies on the genome of this genetically impoverished species. The string graph–based assembly strategy seemed a better choice compared to the conventional de Bruijn graph approach due to the high levels of homozygosity, which is often a hallmark of endemic or endangered species. A consensus reference genome was assembled from sequences of 5 individuals from the southern subspecies (S. p. woodi). In addition, we obtained an additional sequence from 1 sample of the northern subspecies (S. p. paradoxus). The resulting genome assemblies were compared to each other and annotated for genes, with an emphasis on venom genes, repeats, variable microsatellite loci, and other genomic variants. Phylogenetic positioning and selection signatures were inferred based on 4,416 single-copy orthologs from 10 other mammals. We estimated that solenodons diverged from other extant mammals 73.6 million years ago. Patterns of single-nucleotide polymorphism variation allowed us to infer population demography, which supported a subspecies split within the Hispaniolan solenodon at least 300 thousand years ago.

Biochemical and pharmacological characterization of Trimersurus malabaricus snake venom.

Trimeresurus malabaricus is a venomous pit viper species endemic to southwestern part of India. In earlier reports, we have shown that envenomation by T. malabaricus venom leading to strong local tissue damage but the mechanism of action is not clearly revealed. Local tissue damage affected by T. malabaricus venom is of great importance since the poison has serious systemic effects including death in the case of multiple attacks. The present study details the major manifestations of T. malabaricus venom and the induction of local tissue damage, which suggests that most toxins are present in the form of hydrolytic enzymes. Hydrolytic activity of the enzymes was measured and the data indicated that protease and phospholipase A2 activity was high which is responsible for local tissue damage. Furthermore, the role of hydrolytic enzymes in the induction of pathological events such as hemorrhage, edema, myotoxicity, and blood coagulation examination were assessed through animal models.

The role of venom in the hunting and hoarding of prey differing in body size by the Eurasian water shrew, Neomys fodiens

Being venomous should help a predator to maximize foraging gain, reduce handling time, and hoard food. Shrews are a good model for study of the relationship between venomousness and optimal foraging as they have to be highly efficient foragers (because of extremely high energy requirements) and comprise a few venomous species. We hypothesized that venom facilitates shrews to overpower large prey and enables hoarding of (mainly large) prey in a comatose state. We compared hunting and hoarding behaviors of the venomous Neomys fodiens and the nonvenomous Sorex araneus, which were allowed to forage on live prey differing in body size. As we predicted, small invertebrates were immediately consumed by both shrew species, whereas larger ones were immobilized and hoarded. Smaller S. araneus hoarded proportionally more food than larger N. fodiens. Although different ways of prey immobilization were expected (venomous paralyzing by N. fodiens and mechanical damage by S. araneus), both species seemed to use mechanical immobilization. However, N. fodiens required significantly less time than S. araneus to subdue prey of proportionally similar sizes and this difference grew with the increase in prey mass. Only N. fodiens was able to overpower and kill frogs (but not larger toads). We concluded that the relatively weak venom of N. fodiens is helpful in overpowering and hoarding mainly medium-sized prey. Thus, venomousness helps N. fodiens to optimize its foraging as it reduces prey handling time, enables it to gain larger energy portions, and facilitates food hoarding, which reduces foraging time.

First reliable record of the blue-lined octopus, Hapalochlaena fasciata (Hoyle, 1886) (Cephalopoda: Octopodidae), from Jeju Island, Korea

A specimen of the blue-lined octopus, Hapalochlaena fasciata (Hoyle, 1886) was collected from a tidal pool on the southern coast of Jeju Island, Korea, on 10 September 2015 and identified by DNA barcoding. This species is characterized by its blue middle lines on dorsal and lateral mantle and head, with development of numerous small papillae on the mantle, head, and arms. A molecular analysis of the mitochondrial DNA cytochrome oxidase subunit I gene showed that the specimen belonged to H. fasciata with 98.8% sequence similarity. The proposed Korean name is “Pa-ran-seon-mun-eo”. The present study far expanded the geographic distribution of H. fasciata, and further monitoring is to be made for this venomous octopus species.

Potential Environmental and Ecological Effects of Global Climate Change on Venomous Terrestrial Species in the Wilderness

Climate change has been scientifically documented, and its effects on wildlife have been prognosticated. We sought to predict the overall impact of climate change on venomous terrestrial species. We hypothesize that given the close relationship between terrestrial venomous species and climate, a changing global environment may result in increased species migration, geographical redistribution, and longer seasons for envenomation, which would have repercussions on human health. A retrospective analysis of environmental, ecological, and medical literature was performed with a focus on climate change, toxinology, and future modeling specific to venomous terrestrial creatures. Species included venomous reptiles, snakes, arthropods, spiders, and Hymenoptera (ants and bees). Animals that are vectors of hemorrhagic infectious disease (eg, mosquitos, ticks) were excluded. Our review of the literature indicates that changes to climatic norms will have a potentially dramatic effect on terrestrial venomous creatures. Empirical evidence demonstrates that geographic distributions of many species have already shifted due to changing climatic conditions. Given that most terrestrial venomous species are ectotherms closely tied to ambient temperature, and that climate change is shifting temperature zones away from the equator, further significant distribution and population changes should be anticipated. For those species able to migrate to match the changing temperatures, new geographical locations may open. For those species with limited distribution capabilities, the rate of climate change may accelerate faster than species can adapt, causing population declines. Specifically, poisonous snakes and spiders will likely maintain their population numbers but will shift their geographic distribution to traditionally temperate zones more often inhabited by humans. Fire ants and Africanized honey bees are expected to have an expanded range distribution due to predicted warming trends. Human encounters with these types of creatures are likely to increase, resulting in potential human morbidity and mortality. Temperature extremes and changes to climatic norms may have a dramatic effect on venomous terrestrial species. As climate change affects the distribution, populations, and life histories of these organisms, the chance of encounters could be altered, thus affecting human health and the survivability of these creatures.

Scorpion Venom Causes Apoptosis by Increasing Reactive Oxygen Species and Cell Cycle Arrest in MDA-MB-231 and HCT-8 Cancer Cell Lines.

Objectives.The objective of this study was to examine the effect of scorpion venoms on cancer cell progression, apoptosis, and cell cycle arrest. Scorpion venoms are known to possess numerous bioactive compounds that act against cancer progression by inducing apoptosis. In this study, we have taken the venoms from the following 2 species of scorpion—Androctonus crassicauda and Leiurus quinquestriatus—and tested the anticancer properties of the venom against breast and colorectal cancer cell lines.Methods.Milking of scorpion venom and culturing the breast and colorectal cancer cell lines were done according to the standard procedure. The venom cytotoxicity was assessed by MTT methods, and the cellular and nuclear changes were studied with phase contrast and propidium iodide staining, respectively. The cell cycle arrest and accumulation of reactive oxygen species were analyzed on a Muse cell analyzer.Results.The venoms exerted cytotoxic effects on breast and colorectal cell lines in a dose- and time-dependent manner. Enhanced apoptotic cells, increase in reactive oxygen species, and cell cycle arrest were observed after challenging these cell lines with scorpion venoms.Conclusions.Scorpion venom induces apoptosis in breast and colorectal cell lines as reflected by the changes in the cell morphology and cell cycle studies. Furthermore, a high percentage of total reactive oxygen species as well as apoptotic cells also contribute to cell death as observed after venom treatments. To the best of authors’ knowledge, this is the first scientific evidence demonstrating the induction of apoptosis and cell cycle arrest by these species of scorpion venoms.