European Medicinal Leeches-New Roles in Modern Medicine

Exploring a Hirudin variant from nonhematophagous leeches: Unraveling full-length sequence, alternative splicing, function, and potential as a novel anticoagulant polypeptide

ETHNOPHARMACOLOGICAL RELEVANCE

Leeches exhibit robust anticoagulant activity, making them useful for treating cardiovascular diseases in traditional Chinese medicine. Whitmania pigra, the primary source species of leech-derived medicinal compounds in China, has been demonstrated to possess formidable anticoagulant properties. Hirudin-like peptides, recognized as potent thrombin inhibitors, are prevalent in hematophagous leeches. Considering that W. pigra is a nonhematophagic leech, the following question arises: does a hirudin variant exist in this species?

AIM OF THE STUDY

In this study we identified the hirudin-encoding gene (WP_HV1) in the W. pigra genome. The goal of this study was to assess its anticoagulant activity and analyze the related mechanisms.

MATERIALS AND METHODS

In this study, a hirudin-encoding gene, WP_HV1, was identified from the W. pigra genome, and its accurate coding sequence (CDS) was validated through cloning from cDNA extracted from fresh W. pigra specimens. The structure of WP_HV1 and the amino acids associated with its anticoagulant activity were determined by sequence and structural analysis and prediction of its binding energy to thrombin. E. coli was used for the expression of WP_HV1 and recombinant proteins with various structures and mutants. The anticoagulant activity of the synthesized recombinant proteins was then confirmed using thrombin time (TT).

RESULTS

Validation of the WP_HV1 gene was accomplished, and three alternative splices were discovered. The TT of the blank sample exceeded that of the recombinant WP_HV1 sample by 1.74 times (0.05 mg/ml), indicating positive anticoagulant activity. The anticoagulant activity of WP_HV1 was found to be associated with its C-terminal tyrosine, along with the presence of 9 acidic amino acids on both the left and right sides. A significant reduction in the corresponding TT was observed for the mutated amino acids compared to those of the wild type, with decreases of 4.8, 6.6, and 3.9 s, respectively. In addition, the anticoagulant activity of WP_HV1 was enhanced and prolonged for 2.7 s when the lysine-67 residue was mutated to tryptophan.

CONCLUSION

Only one hirudin-encoding variant was identified in W. pigra. The active amino acids associated with anticoagulation in WP_HV1 were resolved and validated, revealing a novel source for screening and developing new anticoagulant drugs.

Starvation-induced changes in the proteome and transcriptome of the salivary glands of leech (Hirudo nipponia)

Hirudo nipponia is an important medicinal animal in China. Its salivary gland secretions contain a variety of protein bioactive substances. Investigations of its salivary glands are of great significance in the study of the medicinal value and mechanism of leech secretions. Illumina RNA-Seq technology was used to perform transcriptome sequencing of salivary gland tissue of H. nipponia under starvation (D30) and fed (D0) states. A total of 2,650 differentially expressed genes (DEGs) were screened. Using the label-free protein quantification technique and bioinformatics analysis, the expression of differentially expressed proteins (DEPs) in the salivary gland tissue of H. nipponia was compared. A total of 2,021 proteins were identified, among which 181 proteins were differentially expressed between the starvation and fed states, with 72 significantly upregulated and 109 significantly downregulated. The salivary glands of H. nipponia synthesized protein-based active substances after 30 days of starvation and adapted to the starvation environment by weakening respiratory activity and reducing metabolic activity to reduce energy expenditure. Energy was produced by glycolysis and the tricarboxylic acid cycle for the synthesis of substances such as antibiotics. This study combined transcriptome and proteome sequencing data to provide a data reference for an in-depth study of the regulatory mechanism of salivary gland secretions of H. nipponia under starvation stress by analyzing DEGs and DEPs.

Unveiling antibiofilm potential: proteins from Priestia sp. targeting Staphylococcus aureus biofilm formation

Staphylococcus aureus is the etiologic agent of many nosocomial infections, and its biofilm is frequently isolated from medical devices. Moreover, the dissemination of multidrug-resistant (MDR) strains from this pathogen, such as methicillin-resistant S. aureus (MRSA) strains, is a worldwide public health issue. The inhibition of biofilm formation can be used as a strategy to weaken bacterial resistance. Taking that into account, we analysed the ability of marine sponge-associated bacteria to produce antibiofilm molecules, and we found that marine Priestia sp., isolated from marine sponge Scopalina sp. collected on the Brazilian coast, secretes proteins that impair biofilm development from S. aureus. Partially purified proteins (PPP) secreted after 24 hours of bacterial growth promoted a 92% biofilm mass reduction and 4.0 µg/dL was the minimum concentration to significantly inhibit biofilm formation. This reduction was visually confirmed by light microscopy and Scanning Electron Microscopy (SEM). Furthermore, biochemical assays showed that the antibiofilm activity of PPP was reduced by ethylenediaminetetraacetic acid (EDTA) and 1,10 phenanthroline (PHEN), while it was stimulated by zinc ions, suggesting an active metallopeptidase in PPP. This result agrees with mass spectrometry (MS) identification, which indicated the presence of a metallopeptidase from the M28 family. Additionally, whole-genome sequencing analysis of Priestia sp. shows that gene ywad, a metallopeptidase-encoding gene, was present. Therefore, the results presented herein indicate that PPP secreted by the marine Priestia sp. can be explored as a potential antibiofilm agent and help to treat chronic infections.

From bloodthirsty parasites to surgical superstars: The humble leech, a suck-cess story in surgical history

This historical review delves into the extensive and intriguing history of leeches in surgery. The utilisation of leeches in medical practice dates back thousands of years, from ancient civilisations to the modern era. The therapeutic properties of leeches have led to their persistent presence in surgical procedures. The 'Age of Leeches' during the 18th and 19th centuries witnessed a heightened utilisation of leeches in surgical treatment, given their perceived ability to promote postoperative wound healing and alleviate blood congestion. However, advancements in medical knowledge subsequently diminished their popularity as emerging technologies overshadowed them. Nevertheless, recent years have witnessed a resurgence in the use of leeches in reconstructive surgery, driven by both a greater understanding of their biological mechanisms and their potential source of therapeutic agents. This historical review provides a comprehensive exploration of the historical timeline, societal perceptions and scientific advancements surrounding the use of leeches in surgical practice.

Topical hypertonic saline as a treatment for ocular and nasal hirudiniasis in a dog

This case report describes ocular and nasal leech infestation (hirudiniasis) in a dog. The patient presented for a suspected ocular foreign body. The patient was sedated to allow proper examination, which revealed a leech foreign body attached to the bulbar conjunctiva adjacent to the inferotemporal limbus of the left eye. A 3.5% hypertonic saline solution was applied topically to the eye in four sequential drops, until the leech detached itself and was removed with a cotton bud. The affected eye was found to have a small corneal ulcer, a small area of scleral haemorrhage, and prominent lymphoid follicles within the third eyelid. Approximately 5 min after the leech was removed, another leech emerged from the left nostril. The patient was sent home on chloramphenicol ointment for treatment of the corneal ulcer, was rechecked 4 days later by an American Board of Veterinary Ophthalmology resident (PM) and found to have a normal ocular exam. This case report highlights that topical hypertonic saline solution (3.5%) can be an effective and easily prepared treatment for ocular and nasal hirudiniasis in veterinary patients.

Case Reports and Experts Opinions about Current Use of Leech Therapy in Dermatology and Cosmetology

This article aimed to determine the experts’ opinion on the use of hirudotherapy in cosmetology, to supplement knowledge, and to identify factors that, in the opinion of experts, affect the effectiveness and frequency of use of this method in eliminating skin problems. The study was conducted using the expert interview method. The research tool was a categorized expert interview questionnaire using the CAWI (Computer Assisted Web Interview) technique. Hirudotherapy is one of the oldest healing methods. The mechanism of action is based on the therapeutic properties of bioactive substances isolated from leech saliva. It has been shown to have a wide range of applications in the treatment of numerous diseases in various fields of medicine, including dermatology and cosmetology. Despite its therapeutic properties and effectiveness, hirudotherapy is a rarely used tool in cosmetology. It has been found effective in the treatment of many dermatoses. The most spectacular effects have been observed in the treatment of rosacea, local inflammations, lipomas, skin scars, hard to heal wounds and contusions.

From ancient leech to direct thrombin inhibitors and beyond: New from old

Medicinal leeches have been used in health care since before written history, with widely varying popularity over the centuries. Nowadays, medicinal leech therapy is mainly used in plastic and reconstructive microsurgery, with new interesting potential therapeutic applications in many other diseases. The leech's best-known salivary product, hirudin - one of the most powerful natural anticoagulants - was the only remedy to prevent blood clotting until the discovery of heparin. Starting from hirudin, pharmacological research succeeded in developing new anticoagulants, which represent a cornerstone of prevention and treatment of thromboembolic disease. While we are perhaps on the threshold of a new era of anticoagulation, with the development of FXI and XII inhibitors and direct reversible covalent thrombin inhibitors, which promise to achieve effective anticoagulation without bleeding risk. This review retraces the intriguing journey of these drugs in cardiovascular disease, highlighting the fil rouge that links the ancient leech to the current and oncoming antithrombotic therapy. We think that knowledge of the past is key to understanding and appreciating the present and to seize future opportunities.

Animal Venoms-Curse or Cure?

An estimated 15% of animals are venomous, with representatives spread across the majority of animal lineages. Animals use venoms for various purposes, such as prey capture and predator deterrence. Humans have always been fascinated by venomous animals in a Janus-faced way. On the one hand, humans have a deeply rooted fear of venomous animals. This is boosted by their largely negative image in public media and the fact that snakes alone cause an annual global death toll in the hundreds of thousands, with even more people being left disabled or disfigured. Consequently, snake envenomation has recently been reclassified by the World Health Organization as a neglected tropical disease. On the other hand, there has been a growth in recent decades in the global scene of enthusiasts keeping venomous snakes, spiders, scorpions, and centipedes in captivity as pets. Recent scientific research has focussed on utilising animal venoms and toxins for the benefit of humanity in the form of molecular research tools, novel diagnostics and therapeutics, biopesticides, or anti-parasitic treatments. Continued research into developing efficient and safe antivenoms and promising discoveries of beneficial effects of animal toxins is further tipping the scales in favour of the “cure” rather than the “curse” prospect of venoms.

Time to Change Theory; Medical Leech from a Molecular Medicine Perspective Leech Salivary Proteins Playing a Potential Role in Medicine

Followed by developing modern medicine, leeches did not have extensive use as before; however, in the late 19th century, they were still used in most countries all over the world. Thus far, leeches were utilized in treating various diseases like skin disorders, arthritis, and cancer. In Egypt, using leeches for treatment dates back to early 1500 BC. A medical leech’s salivary glands involve over 100 bioactive proteins and the salivary gland secretion contains bacteriostatic, analgesic, and anticoagulation influences; with resolving activity, it causes microcirculation disorders elimination, restoring the hurt vascular permeability of organs and tissues, removing hypoxia, decreasing blood pressure and detoxifying the organism by antioxidant paths. The current work reviews the innovative treatment with medical leech, especially proteins in leech saliva extraction (LSE) with high potential in medicine. The virtue of salivary gland secretions which are proteinaceous enzymes, leech acts on various diseases such as venous congestion in reconstructive and plastic surgery, osteoarthritis, cardiovascular diseases caused by blood coagulation disorders, pain management, priapism, macroglossia, cancer complications, wounds and many other. To confirm the potential therapeutic impacts of leech treatment, more studies are required in more extensive areas with more exact methodologies.