Biochemical and Proteomic Characterization, and Pharmacological Insights of Indian Red Scorpion Venom Toxins

A multiplexing immunosensing platform for the simultaneous detection of snake and scorpion venoms: Towards a better management of antidote administration

Envenomation accidents are usually diagnosed at the hospital through signs and symptoms assessment such as short breath, dizziness and vomiting, numbness, swilling, bruising, or bleeding around the affected site. However, this traditional method provides inaccurate diagnosis given the interface between snakebites and scorpion stings symptoms. Therefore, early determination of bites/stings source would help healthcare professionals select the suitable treatment for patients, thus improving envenomation management. In this study, we developed an innovative multiplexing platform based on dual immunosensors for the simultaneous determination of snake and scorpion venoms using a label-free electrochemical platform. The dual immunosensor was fabricated on graphene/gold nanoparticle modified screen-printed electrodes. The electrodes were first modified with two chemical linkers (cysteamine/phenylene diisothiocyanate) to facilitate the immobilization of the antibodies (antivenoms) through covalent binding. The proposed immunosensor was tested with different venoms that specific to six snake species and two scorpion species. The detection was undergone by monitoring the reduction peak current variation after the venom binding using square wave voltammetry, in presence of ferro/ferricyanide redox system. The dual immunosensor enabled a sensitive and selective simultaneous detection of the snake and scorpion species venoms within wide linear ranges in the limits of detection ranging from 0.057 to 0.027 μg/mL. The applicability of the venoms immunosensor has also been evaluated for the detection of snake and scorpion venoms in human serum samples showing high recovery percentages. These achievements show the great potential of our multiplexing approach for the early detection of snake or scorpion envenomation.

Advancements in diagnostic techniques for scorpion venom identification: A comprehensive review

Scorpion envenomation's ignored public health problem in tropical and subtropical countries is alarming. Particularly dangerous for small children and the elderly, it can cause severe problems and even death. Recent studies have proposed the creation of rapid, easy, species-specific, and sensitive detection kits as an alternative to the methods currently used to identify scorpions. Unfortunately, there is currently no commercially available technology for detecting scorpion envenomation in clinical settings, especially in remote tropical health centres. This study delineates the most dangerous scorpion species globally and the advancements in identifying their stings in vitro or in envenomed plasma. Furthermore, we have highlighted the practical challenges associated with scorpion venom detection and the necessity for innovative, expedited, and more accessible detection kits in countries where scorpion envenomation poses a significant issue.

Development of a gold nanoparticle-based novel diagnostic prototype for in vivo detection of Indian red scorpion (Mesobuthus tamulus) venom

Indian red scorpion Mesobuthus tamulus is responsible for substantial mortality in India and Sri Lanka; however, no specific diagnostic method is available to detect the venom of this scorpion in envenomed plasma or body fluid. Therefore, we have proposed a novel, simple, and rapid method for detecting M. tamulus venom (MTV) in the plasma of envenomed animals using polyclonal antibodies (PAb) raised against three modified custom peptides representing the antigenic epitopes of K+ (Tamapin) and Na+ (α-neurotoxin) channel toxins, the two major MTV toxins identified by proteomic analysis. The optimum PAb formulation containing PAb 1, 2, and 3 in proportion (1:1:1, w/w/w) acted synergistically, demonstrating significantly higher immunological recognition of MTV than anti-scorpion antivenom (developed against native toxins) and individual antibodies against peptide immunogens. The PAb formulation could detect MTV optimally in envenomed rat plasma (intravenous and subcutaneous routes) at 30-60 min post-injection. The acetonitrile precipitation method developed in this study to augment the MTV detection sensitivity enriched the low molecular mass peptide toxins in envenomed rat plasma, which was ascertained by mass spectrometry analysis. The gold nanoparticles conjugated PAb formulation, characterised by biophysical techniques such as Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM), demonstrated their interaction with low molecular mass MTV peptide toxins in envenomed rat plasma. This interaction results in the accumulation of the gold nanoparticles, thus leading to signal change in absorbance spectra that can be discerned within 10 min. From a standard curve of MTV spiked plasma, the quantity of MTV in envenomed rat plasma could be determined by gold nanoparticle-PAb formulation conjugate.

The geographical distribution of scorpions, implication of venom toxins, envenomation, and potential therapeutics in Southern and Northern Africa

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.

Scorpion Sting Envenomation, a Neglected Tropical Disease: A Nationwide Survey Exploring Perspectives and Attitudes of Resident Doctors from India

Scorpion sting envenomation (SSE) is a commonly encountered and a significant problem in the tropics, affecting rural and marginalized communities. However, it is not formally listed as a neglected tropical disease (NTD) by the WHO. We designed this cross-sectional study to explore medical graduates' and resident doctors' perspectives on SSE as an NTD and to assess their experiences, knowledge, and confidence in managing these patients. An online questionnaire was developed, validated, and administered to interns and resident doctors across India. Adjusted odds ratios were calculated for factors predicting high self-reported confidence scores for managing scorpion stings using multivariable logistic regression. The final questionnaire contained 26 items including participant background, perspectives about SSE being an NTD, experiences, knowledge, and skills needed to manage, and prevent stings effectively. Of 454 participants, 69% opined that SSE was an NTD, and > 60% felt that SSE was inadequately addressed within undergraduate training. Predictors of high self-reported confidence scores in management competencies were residency in a clinical branch that commonly encountered SSE (internal/emergency medicine or pediatrics, P < 0.0001), having ever managed an SSE patient alone or as a part of a team (P < 0.0001), and attending a class or teaching session on SSE during undergraduate training (P = 0.048). Our results suggest that residents across India believe that there is an urgent need to declare SSE an NTD to increase its visibility, further paving the way for innovative multilevel cross-cutting solutions for mitigation. Designing authentic learning experiences can help produce competent and empathetic physicians in managing and preventing SSE.

A Novel Therapeutic Formulation for the Improved Treatment of Indian Red Scorpion (Mesobuthus tamulus) Venom-Induced Toxicity-Tested in Caenorhabditis elegans and Rodent Models

Indian Red Scorpion (Mesobuthus tamulus) stings are a neglected public health problem in tropical and sub-tropical countries, including India. The drawbacks of conventional therapies using commercial anti-scorpion antivenom (ASA) and α1-adrenoreceptor antagonists (AAA) have prompted us to search for an adequate formulation to improve treatment against M. tamulus stings. Novel therapeutic drug formulations (TDF) of low doses of commercial ASA, AAA, and ascorbic acid have remarkably improved in neutralising the in vivo toxic effects of M. tamulus venom (MTV) tested in Caenorhabditis elegans and Wistar strain albino rats in vivo models. The neutralisation of MTV-induced production of free radicals, alteration of the mitochondrial transmembrane potential, and upregulated expression of genes involved in apoptosis, detoxification, and stress response in C. elegans by TDF surpassed the same effect shown by individual components of the TDF. Further, TDF efficiently neutralized the MTV-induced increase in blood glucose level within 30 to 60 min post-treatment, organ tissue damage, necrosis, and pulmonary oedema in Wistar rats, indicating its clinical application for effecting treating M. tamulus envenomation. This study demonstrates for the first time that C. elegans can be a model organism for screening the neutralization potency of the drug molecules against a neurotoxic scorpion venom.

Ethnomedicines for the treatment of scorpion stings: A perspective study

ETHNOPHARMACOLOGICAL RELEVANCE

Scorpion sting is a public health concern with limited clinical symptomatic treatment. The clinical treatment uses anti-scorpion antivenom and prazosin (α-adrenergic inhibitor), often in combination with insulin, to reduce scorpion venom-induced hyperglycemia and other complications. However, these therapies also possess some limitations, necessitating urgent exploration of ethnomedicines, mainly traditional medicinal plants, to treat scorpion stings. Unfortunately, several conventional treatments are not scientifically validated, thus raising questions about their quality and utility. Therefore, pharmacological re-assessment of such medicinal plants to alleviate scorpion stings' complications is essential.

AIM OF THE STUDY

The principal objectives of this study are to provide a brief overview of medically important scorpions of the world, outline the extant traditional practices, and comprehensively review plants used in conventional ethnic medicines to treat scorpion stings over time. Modern technological advances in identifying and characterizing plant bioactive molecules are also mentioned in this review.

MATERIALS AND METHODS

The traditionally used medicinal plants against scorpion stings were reviewed from the available literature in the database. The Plant List (http://www.theplantlist.org/) was used to validate the scientific names of the plants mentioned in this study. The search targeted literature on conventional treatments and crude plant extracts or their bioactive components with proven neutralization capacity against scorpion stings. Search words used were 'scorpion sting,' 'treatment for a scorpion sting,' 'antivenom and scorpion sting,' 'traditional treatment for scorpion stings, and 'natural compounds against scorpion stings'.

RESULTS

A list of more than 200 medicinal plants traditionally used in several countries for treating scorpion stings is presented in this review. Though some myth-based remedies are practiced to treat scorpion stings, no empirical evidence exists to validate this aspect of traditional knowledge. Only 38 traditional medicinal plant extracts have been tested under in-vivo and in-vitro conditions to determine their neutralization potency of scorpion envenomation. Although a few bioactive plant constituents showing scorpion venom neutralization potency have been characterized, they are not yet commercially available for clinical application.

CONCLUSIONS

There is tremendous potential locked in medicinal plants' traditional knowledge for scorpion envenomation treatment. Translating this knowledge into the clinical application will require pharmacological reassessment, in tandem with isolation and characterization of active compounds to prove their prophylactic prowess. Almost equally important would be the formulation of stringent strategies to conserve such medicinal plants from overexploitation.