Ananteris is a scorpion genus that inhabits dry and seasonal areas of South and Central America. It is located in a distinctive morpho-group of Buthids, the \'Ananteris group\', which also includes species distributed in the Old World. Because of the lack of information on venom composition, the study of Ananteris species could have biological and medical relevance. We conducted a venomics analysis of Ananteris platnicki, a tiny scorpion that inhabits Panama and Costa Rica, which shows the presence of putative toxins targeting ion channels, as well as proteins with similarity to hyaluronidases, proteinases, phospholipases A2, members of the CAP-domain family, and hemocyanins, among others. Venom proteolytic and hyaluronidase activities were corroborated. The determination of the primary sequences carried out by mass spectrometry evidences that several peptides are similar to the toxins present in venoms from Old World scorpion genera such as Mesobuthus, Lychas, and Isometrus, but others present in Tityus and Centruroides toxins. Even when this venom displays the characteristic protein families found in all Buthids, with a predominance of putative Na+-channel toxins and proteinases, some identified partial sequences are not common in venoms of the New World species, suggesting its differentiation into a distinctive group separated from other Buthids.

Scorpions are predatory arachnids whose venomous sting primarily affects people in tropical and subtropical regions. Most scorpion stings can only cause localized pain without severe envenomation. Less than one-third of the stings cause systemic envenoming and possibly lead to death. About 350,000 scorpion stings in Northern Africa are recorded yearly, resulting in about 810 deaths. In Eastern/Southern Africa, there are about 79,000 stings recorded yearly, resulting in 245 deaths. Farmers and those living in poverty-stricken areas are among the most vulnerable to getting stung by scorpions. However, compared to adults, children are at greater risk of severe envenomation. Scorpion venom is made up of complex mixtures dominated by peptides and proteins that confer its potency and toxicity. These venom toxins have intra- and interspecies variations associated with the scorpion\'s habitat, sex, diet, and age. These variations alter the activity of antivenoms used to treat scorpion sting envenomation. Thus, the study of the proteome composition of medically important scorpion venoms needs to be scaled up along their geographical distribution and contributions to envenomation in Southern and Northern Africa. This will help the production of safer, more effective, and broad-spectrum antivenoms within these regions. Here, we review the clinical implications of scorpion sting envenomation in Southern and Northern Africa. We further highlight the compositions of scorpion venoms and tools used in scorpion venomics. We discuss current antivenoms used against scorpion sting envenomation and suggestions for future production of better antivenoms or alternatives. Finally, we discuss the therapeutic properties of scorpion venom.

OBJECTIVE: To describe a young patient with scorpion sting (SS) with typical lesions of urticaria besides the local SS clinical picture.
METHODS: A systematic screening of articles dating from 1966 to 2021 was conducted in the main databases. All articles included the association between SS and urticaria. A new case report is added to the published list.
RESULTS: The literature search found 5 articles with 29 patients with SS and urticaria/allergic reactions. We performed our analysis by adding our present case, resulting in a total of 30 cases. Most were male, and their ages varied from 29 to 48 years. Regarding SS severity, most were mild or moderate. In two articles, patients had more than one sting. The allergic reaction varied from urticaria, pruritus, flushing, angioedema, wheezing, rhinorrhea, sneezing, consciousness alterations, and gastrointestinal and cardiovascular alterations. In 5/6 (83%) articles, the patients were alive at the study time. One subject died from anaphylactic shock.
CONCLUSIONS: The present article systematically reviewed all published cases of SS and allergic reactions to scorpion venom. It is an infrequent association; most patients are male and in the productive age, and reaction may vary from mild to severe, including death.

Studies on the interaction sites of peptide toxins and ion channels typically involve site-directed mutations in toxins. However, natural mutant toxins exist among them, offering insights into how the evolutionary process has conserved crucial sequences for activities and molecular target selection. In this study, we present a comparative investigation using electrophysiological approaches and computational analysis between two alpha toxins from evolutionarily close scorpion species of the genus Tityus, namely, Tst3 and Ts3 from T. stigmurus and T. serrulatus, respectively. These toxins exhibit three natural substitutions near the C-terminal region, which is directly involved in the interaction between alpha toxins and Nav channels. Additionally, we characterized the activity of the Tst3 toxin on Nav1.1-Nav1.7 channels. The three natural changes between the toxins did not alter sensitivity to Nav1.4, maintaining similar intensities regarding their ability to alter opening probabilities, delay fast inactivation, and induce persistent currents. Computational analysis demonstrated a preference for the down conformation of VSD4 and a shift in the conformational equilibrium towards this state. This illustrates that the sequence of these toxins retained the necessary information, even with alterations in the interaction site region. Through electrophysiological and computational analyses, screening of the Tst3 toxin on sodium isoform revealed its classification as a classic α-NaTx with a broad spectrum of activity. It effectively delays fast inactivation across all tested isoforms. Structural analysis of molecular energetics at the interface of the VSD4-Tst3 complex further confirmed this effect.

The Tityus trinitatis, a black scorpion species endemic to the fauna of Trinidad, has been implicated in envenomation with devastating clinical sequelae such as acute pancreatitis and major adverse cardiovascular events. We present the first in-Caribbean case of a 59-year-old Caribbean South Asian male with human immunodeficiency virus who presented with a non-ST-segment-elevation acute coronary syndrome after being stung, which was managed with comprehensive, guideline-directed medical therapy. The clinician should be cognizant of scorpion-induced acute coronary syndrome (ACS) as a potential sequela of envenomation and its clinical management.

Over 400 million years old, scorpions represent an ancient group of arachnids and one of the first animals to adapt to life on land. Presently, the lack of available genomes within scorpions hinders research on their evolution. This study leverages ultralong nanopore sequencing and Pore-C to generate the first chromosome-level assembly and annotation for the desert hairy scorpion, Hadrurus arizonensis. The assembled genome is 2.23 Gb in size with an N50 of 280 Mb. Pore-C scaffolding reoriented 99.6% of bases into nine chromosomes and BUSCO identified 998 (98.6%) complete arthropod single copy orthologs. Repetitive elements represent 54.69% of the assembled bases, including 872,874 (29.39%) LINE elements. A total of 18,996 protein-coding genes and 75,256 transcripts were predicted, and extracted protein sequences yielded a BUSCO score of 97.2%. This is the first genome assembled and annotated within the family Hadruridae, representing a crucial resource for closing gaps in genomic knowledge of scorpions, resolving arachnid phylogeny, and advancing studies in comparative and functional genomics.

A new species, Scorpiops (Euscorpiops) krachansp. nov., belonging to the family Scorpiopidae Kraepelin, 1905 is described based on three adult males and one adult female collected in the Kaeng Krachan National Park, Phetchaburi Province, Thailand. The new species presents most features exhibited by scorpions of the subgenus Euscorpiops and can be characterized notably by a very small size, a sexual dimorphism strongly marked with male pedipalps elongated, a distinct trichobothrial pattern and other morphological features. This new taxon may represent one endemic element for the scorpion fauna of Thailand. Aspects of the ecology and distribution of the new species are discussed and compared with that of other relative Scorpiops species.

Epilepsy, as a neurological disease, can be defined as frequent seizure attacks. Further, it affects many other aspects of patients\' mental activities, such as learning and memory. Scorpion venoms have gained notice as compounds with potential antiepileptic properties. Among them, Buthotus schach (BS) is one of the Iranian scorpions studied by Aboutorabi et al., who fractionated, characterized, and tested this compound using electrophysiological techniques in brain slices (patch-clamp recording). In the present study, the fraction obtained from gel electrophoresis was investigated through behavioral and electrophysiological assays. At first, ventricular cannulation was performed in rats, and then the active fraction (i.e., F3), carbamazepine, and the vehicle were microinjected into the brain before seizure induction by the subcutaneous (SC) injection of pentylenetetrazol (PTZ). Seizure behaviors were scaled according to Racine stages. Memory and learning were evaluated using the Y-maze and passive avoidance tests. Other groups entered evoked field potential recording after microinjection and seizure induction. Population spike (PS) and field excitatory postsynaptic potential (fEPSP) were measured. The F3 fraction could prevent the fifth stage and postpone the third stage of seizure compared to the control (carbamazepine) group. There was no significant improvement in memory and learning in the group treated with the F3 fraction. Also, PS amplitude and fEPSP slope increased significantly, and long-term potentiation was successfully formed after the high-frequency stimulation of the performant pathway. Our results support the antiepileptic effects of the F3 fraction of BS venom, evidenced by behavioral and electrophysiological studies. However, the effects of this fraction on memory and learning were not in the same direction, suggesting the involvement of two different pathways.

BACKGROUND: Takotsubo syndrome is comparable to microvascular acute coronary syndrome. It may partly share the same pathophysiology debated during scorpion envenomation (SE), with an adrenergic storm, without myocardial infarction due to the absence of coronary artery stenosis. Takotsubo cardiomyopathy can help to better understand the pathophysiology of cardiac involvement during scorpion envenomation. However, Takotsubo syndrome seems to be underestimated in the literature in patients suffering from cardiac failure following SE.
METHODS: In this review, we aimed to detail all described cases, the mechanism, and outcomes of scorpion envenomation complicated by Takotsubo cardiomyopathy. We used the PubMed database by using the following keywords in MeSH research: scorpion envenomation, Takotsubo cardiomyopathy, and Takotsubo syndrome.
RESULTS: The literature analysis showed the existence of only four cases of confirmed Takotsubo cardiomyopathy following severe SE. All four patients developed a transient reversible left ventricular systolic dysfunction in the absence of coronary artery disease, following a positive history of scorpion envenomation. A cardiac MRI was performed in all cases, showing a ballooning in the left ventricle associated with a left ventricular ejection fraction in all cases. All patients were improved under symptomatic treatment, and complete recovery of the wall motion was observed.
CONCLUSIONS: Takotsubo syndrome, although not often reported in the literature in severe SE, can represent an effective hypothesis explaining the pathophysiology of cardiac involvement during SE. In severe scorpion envenomation, multiple mechanisms exist and can explain the development of Takotsubo syndrome. Its management is based on oxygen, with invasive or non-invasive ventilator support in patients with respiratory failure and/or cardiogenic shock. Beta-blockers, mineralocorticoid receptor antagonists, and diuretics are usually used in Takotsubo syndrome. However, in severe scorpion envenomation, all reported cases of Takotsubo cardiomyopathy are associated with cardiogenic shock and acute pulmonary edema. As a consequence, we advise the use of Dobutamine since it has already been confirmed that cardiac dysfunction following scorpion envenomation improves well and safely under Dobutamine infusion.

The human body is affected by environmental factors. The dynamic balance between the organism and its environment results from the influence of natural, anthropogenic and social aspects. The factors of exogenous origin determine development of adaptive changes. The present article summarises the mechanisms of animal venom toxins and homeostasis disruption in the body of mammals. The mechanisms underlying pathological changes are associated with shifts in biochemical reactions. Components of the immune, nervous and endocrine systems are key in the host defense and adaptation processes in response to venom by triggering signalling pathways (PI3kinase pathway, arachidonic acid cascade). Animal venom toxins initiate the development of inflammatory processes, the synthesis of pro-inflammatory mediators (cytokines), ROS, proteolytic enzymes, activate the migration of leukocytes and macrophages. Keratinocytes and endothelial cells act as protective barriers under the action of animal venom toxins on the body of mammals. In addition, the formation of pores in cell membranes, structural changes in cell ion channels are characteristic of the action of animal venom toxins.