ciało-człowieka: Leech

Evidence: 100 • authority: 72

Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodies that can lengthen and contract. Both groups are hermaphrodites and have a clitellum, but leeches typically differ from the oligochaetes in having suckers at both ends and ring markings that do not correspond with their internal segmentation. The body is muscular and relatively solid; the coelom, the spacious body cavity found in other annelids, is reduced to small channels. The majority of leeches live in freshwater habitats, while some species can be f…

Evidence: 61 • authority: 94

European medicinal leeches of the genus Hirudo are blood-feeding annelids. The most relevant species are H. orientalis (Asian leech), H. medicinalis (European leech) and H. verbana (Hungarian leech). All three species are ectoparasites that live in freshwater ponds and slowly flowing streams, where they locate their vertebrate hosts by sensing heat, chemicals or movement [ 1 , 2 ]. Leeches attach to the host body surface and cut the skin using hundreds of calcified teeth [ 3 ]. They can then draw blood for up to one hour while secreting saliva into the wound. The secreted salivary proteins and peptides reach the vascular system of the host via thousands of tiny salivary gland cell ducts [ 4 ]. After ingestion by the leech, the host blood is compressed in the crop by the excretion of water and salts [ 5 , 6 ]. The remaining highly viscous blood comprises plasma proteins and blood cells and can be stored in the crop for up to one year [ 7 ]. It is thought that the morphology of the concentrated erythrocytes remains stable during storage [ 8 ], which means that proteolysis induced by host proteases released from leukocytes is inhibited [ 5 ]. Furthermore, leeches inevitably make contact with (and thus ingest) some bacteria on the surface of the host’s skin during feeding, but the stored blood does not become overrun with pathogens. Indeed, foremost symbiotic core bacteria such as Aeromonas veronii , A. hydrophila and Rikinella -like species survive in the alimentary tract of the leech [ 9 , 10 , 11 ]. It is supposed that symbionts like A. veronii support the digestion of host blood by facilitating hemolysis [ 10 , 12 , 13 ] and may also help to suppress the growth of other bacteria in the crop of the leech [ 9 ]. In most parasitic leeches the host blood is stored in the crop, while food digestion and the absorption of nutrients occur predominantly in the intestine. It can be assumed that medicinal leech enzymes (e.g., endopeptidases, aminopeptidases, phosphatases) promote digestion processes [ 14 ]. Antagonistic interactions between parasites and their hosts have led to an evolutionary “arms race”, during which ectoparasites adapted to feed on host body fluids [ 42 , 43 ]. To ingest and digest host blood, medicinal leeches synthesize more than 100 salivary proteins and peptides [ 44 , 45 , 46 , 47 ]. The molecules are secreted during feeding and target physiological pathways involved in host defense, working as analgesics (kininases), anticoagulants (hirudin, calin, saratin and apyrase), anti-inflammatories (eglins, bdellins and tryptase inhibitor), cell matrix-degrading proteins (hyaluronidase) or antimicrobials [ 7 , 45 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 ]. Salivary transcriptome data from Macrobdella decora [ 59 ] and Hirudo nipponia [ 60 ], as well as expressed sequence tag libraries constructed from the salivary glands of H. verbana , M. decora and Aliolimnatis fenestrata [ 61 ], provided insight into the spectrum proteins found in leech saliva. For European medicinal leeches, the combined transcriptomic analysis of salivary gland cells and proteomic analysis of saliva in H. medicinalis , H. orientalis and H. verbana revealed a much wider repertoire of components than previously known [ 44 ], indicating that only ~15% of the salivary proteins in these species were identified and characterized ( Table 1 ). Analysis of the salivary transcriptomes of H. medicinalis , H. orientalis and H. verbana revealed the presence of transcripts representing 189, 86 and 344 salivary proteins, respectively [ 44 ]. The three closely related species were found to share 39 orthologous clusters, whereas 50 orthologous clusters were shared by any two of the three species [ 44 ]. Many of these newly discovered leech salivary proteins are either associated with blood feeding or related to proteins found in animal venoms [ 44 ]. The salivary proteins predicted from transcriptomic and proteomic data can be assigned to various functional groups based on their structural similarities, including metalloproteases representing the M12, M13 and M28 families, hyaluronidases, apyrases, adenosine deaminases, antistasins, cysteine-rich secretory proteins (CRISPs), eglins, cystatins, PAN/apple domain proteins, α2-macroglobulins, low-density lipoprotein receptors, R-type lectins, and salivary proteins containing a von Willebrand factor type A (vWA) domain. These proteins are likely to be involved in the regulation of blood coagulation, the temporary adjustment of blood pressure, the regulation of inflammation, the suppression of microbial growth or the digestion of blood in the crop [ 44 ]. Interestingly, differential gene expression analysis indicated that genes encoding salivary proteins, such as hirudin, eglins, saratins and destabilases, were also expressed in other leech tissues, showing that at least some leech “salivary proteins” are not restricted to the saliva and may have additional physiological functions [ 44 ]. Some leech-specific anticoagulants were also found in leeches that do not feed on blood, such as Whitmania pigra [ 62 ]. Interestingly, these anticoagulants were upregulated after feeding [ 62 ] just as they are in blood-feeding leeches [ 63 ].

Evidence: 70 • authority: 90

Further evidence of the southern Mediterranean medicinal leech Hirudo verbana (Annelida, Hirudinea) feeding on fish, with a review of the use of fish hosts by Hirudo spp.. Although often considered primarily hematophagous on mammalian blood, the leeches belonging to the genus Hirudo can feed on several other vertebrate hosts. However, to date, little is known about the feeding ecology of medicinal leeches in the wild, and the few available observations mostly deals with the European medicinal leech, Hirudo medicinalis. Since even closely related Hirudo species have different functional morphology and ecological preferences, the observations carried out on one species cannot be automatically…

Evidence: 67 • authority: 92

The great diversity: monomeric and oligomeric hirudins, hirudin-like factors and decorsins in the Asian medicinal leeches Hirudo nipponia and Hirudo tianjinensis.. Medicinal leeches express a broad variety of anticoagulants and other bioactive factors that are involved in the blood feeding process. For most of the anticoagulants, several genes exist that may encode isoforms of the respective proteins, including hirudins and decorsins. Decorsins negatively affect platelet aggregation, whereas hirudins are potent thrombin inhibitors. Both factors belong to the hirudin superfamily that also includes the group of hirudin-like factors, and all hematophagous leeches analyzed so far contain severa…

Evidence: 61 • authority: 72

Hirudin is a naturally occurring peptide in the salivary glands of blood-sucking leeches (such as Hirudo medicinalis) that has a blood anticoagulant property. This is essential for the leeches' habit of feeding on blood, since it keeps a host's blood flowing after the worm's initial puncture of the skin.

Evidence: 56 • authority: 90

Notwithstanding the significance of the European medicinal leech Hirudo medicinalis Linnaeus, 1758 as a medical tool from antiquity through modern science-based medicine, it is remarkable that this species’ repertoire of anticoagulants and other bioactive salivary proteins has escaped published in-depth investigation (but see 1 ). In order to maintain blood flow in the tissues surrounding the incision wounds during their extended periods of feeding and, importantly, keeping the blood from clotting inside of the crop during the periods of digestion, bloodfeeding leeches secrete a variety of bioactive compounds from their salivary glands. Over 20 different compounds relating to antihemsotasis have been isolated from leech saliva including, for example, direct thrombin inhibitors, factor Xa inhibitors, trypsin inhibitors, endoglucuronidases and antiplatelet proteins 2 , 3 . Despite its historical significance in medicine, the detailed composition of the anticoagulant profile of Hirudo medicinalis Linnaeus, 1758 has escaped scrutiny insofar as modern studies have been concerned primarily with the commercially available species Hirudo verbana (Carena, 1820) 4 , 5 , 6 , 7 ; but see also 1 , 8 . Whereas H. medicinalis was long thought to be the centerpiece for the clinical application of leeches in hospital settings, recent investigations have shown that Hirudo verbana is far more commonly employed for this purpose 4 yet sold under the name H. medicinalis ; this confusion also prompted the designation of a neotype specimen for H. medicinalis in order to ameliorate future taxonomic confusion 9 . The utility of leeches in modern medicine focuses on post-surgical procedures, chiefly following digit replantation or skin grafting surgery 10 , 11 wherein the build-up of blood in the extremities and resulting congestion of the veins is relieved by their application. By contrast, medieval medicinal practices, the pinnacle of leech-centric phlebotomy, focused on restoring the balance between bodily humors to treat or prevent a variety of conditions 12 . The exceedingly frequent use of leeches caused overharvesting of several species, including Hirudo medicinalis 13 . Indeed, such was the level of harvesting in the 18 th and 19 th centuries that the collection of both H. medicinalis and H. verbana are still protected and governed by the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) (see 14 for an in-depth treatise of the species). Our draft genome for Hirudo medicinalis and in-depth look at the anticoagulant repertoire in this species provides fodder for comparative studies of anticoagulants in medicinal leech species. High-throughout sequencing employing the 10X Chromium platform allowed us to sequence the genome to an estimated 79–94% completion and evinced 18 separate anticoagulant-related orthologues (or putative orthologues) with BLAST matches against eglin C, destabilase I, ghilanten, leech-derived tryptase inhibitor (LDTI), guamerin, cystatin, hirudin, ficolin, Kazal-type serine protease inhibitors (serpins), C-type lectin, manillase, bdellin, piguamerin, antistasin, bdellastasin and an unidentified thrombininhibitor (Table 1 ). In addition, our searches found robust hits against 23 other anticoagulant-related proteins from non-leech taxa. Several of the sequences possessed signal peptide regions at the 5’-end, indicating their secretion from the unicellular salivary glands. Although BLAST-based orthology statements have been commonplace in leech anticoagulant studies for almost a decade, without complementary phylogenetic analyses of putative orthologues, the robustness of such statements can be questioned 20 . Following the phylogenetic analyses presented here, it seems likely that 15 of the 16 leech-derived proteins (note that neither lefaxin nor the unidentified thrombin inhibitor was placed in a phylogenetic context due to the uncertainty of their identity and, therefore, comparative data) are indeed orthologous with their top BLAST hits, and the same number for non-leech proteins was 17 out of 23. A large body of literature supports the notion that phylogenetic analyses are needed for accurate orthology and paralogy statements ( e.g . 43 , 44 , 45 , 46 ). Given that accurate orthology statements were only made possible via phylogenetic analyses, the present study underscores the importance of incorporating such analyses into any study where orthology is not determined a priori . However, the lack of appropriate outgroups for leech anticoagulants presents its own set of issues and certainly exacerbates rapid and accurate orthology determination. In this study, we assumed that H. medicinalis -derived proteins that formed a clan (equivalent to a monophyletic group in rooted phylogenies) with its archetypal variant (a protein with demonstrated anticoagulant capabilities) was indeed orthologous to that anticoagulant. The levels of potency in preventing blood clotting for each of our newly sequenced proteins remains to be investigated. The European medicinal leech has been used for medicinal purposes for millennia, and continues to be used today in modern hospital settings. Its utility is granted by the extremely potent anticoagulation factors that the leech secretes into the incision wound during feeding and, although a handful of studies have targeted certain anticoagulants, the full range of anticoagulation factors expressed by this species remains unknown. Here, we present the first draft genome of the European medicinal leech, Hirudo medicinalis , and estimate that we have sequenced between 79–94% of the full genome. Leveraging these data, we searched for anticoagulation factors across the genome of H. medicinalis . Following orthology determination through a series of BLAST searches, as well as phylogenetic analyses, we estimate that fully 15 different known anticoagulation factors are utilized by the species, and that 17 other proteins that have been linked to antihemostasis are also present in the genome. We underscore the utility of the draft genome for comparative studies of leeches and discuss our results in an evolutionary context.

Evidence: 56 • authority: 72

Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice by certain animals of feeding on blood (from the Greek words αἷμα haima "blood" and φαγεῖν phagein "to eat"). Since blood is a fluid tissue rich in nutritious proteins and lipids that can be taken without great effort, hematophagy is a preferred form of feeding for many small animals, such as worms and arthropods. Some intestinal nematodes, such as Ancylostomatids, feed on blood extracted from the capillaries of the gut, and about 75 percent of all species of leeches (e.g., Hirudo medicinalis) are hematophagous. The spider Evarcha culicivora feeds indirectly on vertebrate blood by specializing on blood-filled femal…

Evidence: 51 • authority: 92

Comparative Study of Leech-Derived Tryptase Inhibitor Genes in Four Medicinal Leech Species.. Leeches are aquatic annelids of significant medicinal value, known to produce a variety of antithrombotic proteins. However, the extent of interspecies variation in these bioactive components remains poorly understood. In this study, next-generation sequencing and the Pichia pastoris eukaryotic expression system were employed to systematically analyze the diversity of leech-derived tryptase inhibitor (LDTI) genes and their functional activities across four dominant medicinal leech species: Hirudinaria manillensis , Hirudo nipponia , Whitmania pigra , and Whitmania laevis . Our results revealed a sl…

Evidence: 51 • authority: 72

Macromyzon (meaning "large sucker") is an extinct genus of basal leech (Hirudinea) known from the lower Silurian Waukesha Biota. A single species is currently known, Macromyzon siluricus, which was discovered in strata belonging to the Telychian-aged Brandon Bridge Formation in Wisconsin, United States. Originally discovered alongside the Waukesha Biota in 1985, this taxon was not properly described until 2025. The description paper, which was published by De Carle et al., (2025), found that this taxon was a member of the hirudinide stem-group, splitting off before crown-group leeches evolved. Macromyzon is the oldest known leech in the fossil record, the oldest known complete body fossil f…

Evidence: 51 • authority: 94

Complementary medicine methods have a long history, but modern medicine has just recently focused on their possible modes of action. Medicinal leech therapy (MLT) or hirudotherapy, an old technique, has been studied by many researchers for possible effects on various diseases such as inflammatory diseases, osteoarthritis, and after different surgeries. Hirudo medicinalis has widest therapeutic usage among the leeches, but worldwide, many different species were tested and studied. Leeches secrete more than 20 identified bioactive substances such as antistasin, eglins, guamerin, hirudin, saratin, bdellins, complement, and carboxypeptidase inhibitors. They have analgesic, anti-inflammatory, platelet inhibitory, anticoagulant, and thrombin regulatory functions, as well as extracellular matrix degradative and antimicrobial effects, but with further studies, the spectrum of effects may widen. The technique is cheap, effective, easy to apply, and its modes of action have been elucidated for certain diseases. In conclusion, for treatment of some diseases, MLT is not an alternative, but is a complementary and/or integrative choice. MLT is a part of multidisciplinary treatments, and secretes various bioactive substances. These substances vary among species and different species should be evaluated for both treatment capability and their particular secreted molecules. There is huge potential for novel substances and these could be future therapeutics. Leeches live in fresh water and are segmented, hermaphrodite, carnivorous worms. They are sensitive to vibrations on the water, touch, light, heat, sound, and various chemicals. They are multisegmented, including “brain parts”, and each segment has different organs such as ganglions and testicles. Two sucker parts work for creeping and adherence; the anterior one has three jaws including many teeth. They generally bite warm parts of the host and suck its blood with rhythmic contractions. 3 , 5 Feeding usually takes almost 40 minutes and a leech digests 10–15 mL of blood per feeding. Digestion is achieved by many enzymes and mutual microorganisms such as Aeromonas hydrophila and Pseudomonas hirudinia . 6 , 7 Medicinal leech therapy (MLT) or hirudotherapy is a kind of complementary and integrative treatment method applied with blood-sucking leeches. One or more leeches are attached to the skin of problematic area and the purpose is to gain potential utilities of leech saliva that is secreted while the leeches are feeding. MLT has been used for centuries and the term leech was provided from the word “laece” (physician). The first recorded applications were observed in ancient Eygpt. 1 , 2 In addition, Chinese, Arabic, Anglo-Saxon, Ancient Greek, and Roman medical records have many references to MLT. In 17th century Europe, MLT reached its widest area of application. 1 , 3 Since the 1900s, attention of medical professionals has decreased, but in the last 30 years, MLT has become an important part of much scientific research. 1 , 4

Evidence: 51 • authority: 92

Predictive Distribution Modeling of the Medicinal Leech <i>Hirudo verbana</i> Carena, 1820 (Hirudinea, Hirudinidae) in Sicily: Implications for Conservation.. Hirudo verbana , a medicinal leech species of conservation concern, has long been considered rare and fragmented across its distribution range due to overexploitation and habitat alteration. In this study, we present the first predictive distribution model for H. verbana in Sicily, combining field occurrence data (time: 1980-2024) with environmental variables using an ensemble species distribution modeling (SDM) framework. Unlike its typical occurrence in temperate lowland wetlands of central-eastern Europe, the species in…

Evidence: 51 • authority: 90

New distributional data for the Mediterranean medicinal leech Hirudo verbana Carena, 1820 (Hirudinea, Hirudinidae) in Italy, with a note on its feeding on amphibians. Scarce data are currently available about the distribution of the Mediterranean medicinal leech Hirudo verbana in Italy, and most of the known occurrence localities are based on records collected in the nineteenth and the first half of the twentieth century, which were not confirmed in the last decades, mostly due to a lack of surveys. Accordingly, the available knowledge on the distribution of the species is far from being updated and representative, although a significant negative trend of H. verbana throughout the country i…