Hirudin enhances perforator flap survival: Clinical application report and mechanistic exploration.

BACKGROUND AND PURPOSE: Hirudin, a potent anticoagulant, is used in traditional Chinese medicine (TCM) to treat thrombotic conditions and prevent postoperative thrombosis. Coagulation-related vascular complications are a common cause of perforator flaps failure. This study explores hirudin's potential to enhance flap growth by mitigating coagulation-related issues. MATERIALS AND METHODS: Patients were divided into GroupⅠ(hirudin group) and GroupⅡ(control). Laboratory tests covered red blood cell count (RBC), hematocrit (HCT), platelet count (PLT), monocyte count (MONO), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), and D-Dimer. Clinical parameters, including capillary refill time (CRT), flap swelling, and survival status, were evaluated. Animal experiments used Sprague-Dawley (SD) rats to establish random skin flaps. The experimental side received hirudin injection, while the control side received saline. Flaps were photographed to calculate survival rate, and CD31 immunohistochemical (IHC) analysis was performed to calculate microvessel density (MVD). RESULTS: The study, with 29 patients, found significant CRT differences between groups on postoperative days 2 and 6 (p = 0.027; p = 0.019), favoring GroupⅠ. Swelling severity varied significantly over time; GroupⅡhad more pronounced swelling. GroupⅠshowed superior flap growth with fewer complications, statistically significant (p = 0.033). Specific lab indicators (MONO, PT, and FIB) were significant at certain times. In animal experiments, the experimental side consistently had higher flap survival and slightly increased CD31 expression at various times, with higher MVD on days 2 and 6. CONCLUSIONS: Hirudin enhances flap survival through diverse mechanisms, supporting its role as a complementary approach in perforator flap surgeries.

Recombinant hirudin attenuates pulmonary hypertension and thrombosis in acute pulmonary embolism rat model.

Background: Acute pulmonary embolism (APE) is classified as a subset of diseases that are characterized by lung obstruction due to various types of emboli. Current clinical APE treatment using anticoagulants is frequently accompanied by high risk of bleeding complications. Recombinant hirudin (R-hirudin) has been found to have antithrombotic properties. However, the specific impact of R-hirudin on APE remains unknown. Methods: Sprague-Dawley (SD) rats were randomly assigned to five groups, with thrombi injections to establish APE models. Control and APE group rats were subcutaneously injected with equal amounts of dimethyl sulfoxide (DMSO). The APE+R-hirudin low-dose, middle-dose, and high-dose groups received subcutaneous injections of hirudin at doses of 0.25 mg/kg, 0.5 mg/kg, and 1.0 mg/kg, respectively. Each group was subdivided into time points of 2 h, 6 h, 1 d, and 4 d, with five animals per point. Subsequently, all rats were euthanized, and serum and lung tissues were collected. Following the assessment of right ventricular pressure (RVP) and mean pulmonary artery pressure (mPAP), blood gas analysis, enzyme-linked immunosorbnent assay (ELISA), pulmonary artery vascular testing, hematoxylin-eosin (HE) staining, Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining, immunohistochemistry, and Western blot experiments were conducted. Results: R-hirudin treatment caused a significant reduction of mPAP, RVP, and Malondialdehyde (MDA) content, as well as H2O2 and myeloperoxidase (MPO) activity, while increasing pressure of oxygen (PaO2) and Superoxide Dismutase (SOD) activity. R-hirudin also decreased wall area ratio and wall thickness to diameter ratio in APE rat pulmonary arteries. Serum levels of endothelin-1 (ET-1) and thromboxaneB2 (TXB2) decreased, while prostaglandin (6-K-PGF1α) and NO levels increased. Moreover, R-hirudin ameliorated histopathological injuries and reduced apoptotic cells and Matrix metalloproteinase-9 (MMP9), vascular cell adhesion molecule-1 (VCAM-1), p-Extracellular signal-regulated kinase (ERK)1/2/ERK1/2, and p-P65/P65 expression in lung tissues. Conclusion: R-hirudin attenuated pulmonary hypertension and thrombosis in APE rats, suggesting its potential as a novel treatment strategy for APE.

Hirudin in the Treatment of Chronic Kidney Disease.

Chronic kidney disease (CKD) is a common public health concern. The global burden of CKD is increasing due to the high morbidity and mortality associated with it, indicating the shortcomings of therapeutic drugs at present. Renal fibrosis is the common pathology of CKD, which is characterized by glomerulosclerosis, renal tubular atrophy, and renal interstitial fibrosis. Natural hirudin is an active ingredient extracted from Hirudo medicinalis, which has been found to be the strongest natural specific inhibitor of thrombin. Evidence based on pharmacological data has shown that hirudin has important protective effects in CKD against diabetic nephrology, nephrotic syndrome, and renal interstitial fibrosis. The mechanisms of hirudin in treating CKD are mainly related to inhibiting the inflammatory response, preventing apoptosis of intrinsic renal cells, and inhibiting the interactions between thrombin and protease-activated receptors. In this review, we summarize the function and beneficial properties of hirudin for the treatment of CKD, and its underlying mechanisms.

Research progress on the treatment of diabetic nephropathy with leech and its active ingredients.

Diabetic nephropathy (DN) is a major microvascular complication of diabetes and a common cause of chronic kidney disease. There is currently a lack of effective treatments for DN, and the prognosis for patients remains poor. Hirudin, one of the primary active components derived from leeches, demonstrates anti-coagulant, anti-fibrotic, anti-thrombotic, and anti-inflammatory properties, exhibiting significant protective effects on the kidneys. In recent years, there has been a surge of interest in studying the potential benefits of hirudin, especially in its role in the management of DN. This article delves into the mechanisms by which hirudin contributes to the treatment of DN and its clinical efficacy.

Leech Application-related Upper Gastrointestinal Bleeding: A Case Report.

Leech therapy (Hirudotherapy) is a method used in the treatment of many diseases since ancient times. Although many complications have been reported following the use of this method, no systemic life-threatening bleeding has yet been described. A-43-year-old male patient was diagnosed with upper gastrointestinal bleeding following leech application that he had received for infertility one week earlier. The complications of hirudotherapy typically spontaneously improve due to the local effects of this treatment. The most frequently reported complications are local infections, and less commonly allergies and prolonged local bleeding can occur. However, in this case report, we describe a life-threatening upper gastrointestinal bleeding as a new complication. Gastrointestinal bleeding appearing a week after leech therapy does not necessarily mean that leeches caused gastrointestinal bleeding in this case. Nevertheless, considering the development time of gastrointestinal bleeding, it can be deduced that it was possibly due to hirudotherapy. Patients should be informed about alarming symptoms that can indicate complications following leech application.

Mechanism of Hirudo in Treatment of Stroke： A Review / 中国实验方剂学杂志

Stroke is one of the most common cerebrovascular diseases， including hemorrhagic stroke and ischemic stroke. From a modern medical perspective， stroke is caused by cerebrovascular damage or embolism leading to impaired blood circulation. From the traditional Chinese medicine （TCM） perspective， the pathogenesis of this disease is mainly due to the disorder of Qi and blood， which ascend to the brain， causing either blood extravasation or blockage of brain collaterals. Stasis is a pathological factor that runs throughout the entire course of stroke， and the method of promoting blood circulation and resolving stasis has been a core treatment for stroke for a long time. Hirudo， as a traditional insect drug， has shown good effects in promoting blood circulation and resolving stasis. Modern pharmacological research has confirmed that Hirudo contains anticoagulant components， which provide significant advantages in dissolving thrombi in ischemic stroke and facilitating hematoma absorption in hemorrhagic stroke. Hirudo and its related preparations have been proven to exert an anti-stroke effect through anticoagulation， anti-thrombosis， and protection of vascular endothelium. As a result， they have been widely used in the treatment of stroke. This article explored the theoretical basis and research status of using Hirudo for treating stroke based on its main active components and hemostatic properties and summarized the current research status of commonly used Hirudo-based formulations and preparations， aiming to provide references for the involvement of Hirudo in stroke treatment.

Make it double: identification and characterization of a Tandem-Hirudin from the Asian medicinal leech Hirudinaria manillensis.

Haematophagous leeches express a broad variety of secretory proteins in their salivary glands, among them are hirudins and hirudin-like factors. Here, we describe the identification, molecular and initial functional characterization of Tandem-Hirudin (TH), a novel salivary gland derived factor identified in the Asian medicinal leech, Hirudinaria manillensis. In contrast to the typical structure of hirudins, TH comprises two globular domains arranged in a tandem-like orientation and lacks the elongated C-terminal tail. Similar structures of thrombin inhibitors have so far been identified only in kissing bugs and ticks. Expression of TH was performed in both cell-based and cell-free bacterial systems. A subsequent functional characterization revealed no evidence for a thrombin-inhibitory potency of TH.

Life without blood: Molecular and functional analysis of hirudins and hirudin-like factors of the Asian non-hematophagous leech Whitmania pigra.

BACKGROUND: Several leech species of the genera Hirudo, Hirudinaria, and Whitmania are widely used in traditional Chinese medicine (TCM) for the oral treatment of disorders associated with blood stasis. Among them, the non-hematophagous leech Whitmania pigra expresses a variety of components that have the potential to act on the vertebrate blood coagulation system. OBJECTIVE: Whether the thrombin inhibitor hirudin, probably the most prominent leech-derived anticoagulant, is actually present in Whitmania pigra, is still a matter of debate. To answer that open question was the aim of the study. METHODS: We identified several putative hirudin-encoding sequences in transcriptome data of Whitmania pigra. Upon gene synthesis and molecular cloning the respective recombinant proteins were expressed in Escherichia coli, purified, processed, and eventually functionally characterized for thrombin-inhibitory potencies in coagulation assays. RESULTS: We were successful in the identification and functional characterization of several putative hirudins in Whitmania pigra. Some, but not all, of these factors are indeed thrombin inhibitors. Whitmania pigra hence expresses both hirudins (factors that inhibit thrombin) and hirudin-like factors (that do not or only very weakly inhibit thrombin). Furthermore, we revealed the exon/intron structures of the corresponding genes. Coding sequences of some putative hirudins of Whitmania pigra were present also in transcriptome datasets of Hirudo nipponia, a hematophagous leech that is likewise used in TCM. CONCLUSIONS: Based on both structural and functional data we provide very strong evidence for the expression of hirudins in Whitmania pigra. This is the first description of hirudins in a non-hematophagous leech.

Short tail stories: the hirudin-like factors HLF6 and HLF7 of the Asian medicinal leech, Hirudinaria manillensis.

The leech-derived hirudins and hirudin-like factors (HLFs) share a common molecule structure: a short N-terminus, a central globular domain, and an elongated C-terminal tail. All parts are important for function. HLF6 and HLF7 were identified in the Asian medicinal leech, Hirudinaria manillensis. The genes of both factors encode putative splice variants that differ in length and composition of their respective C-terminal tails. In either case, the tails are considerably shorter compared to hirudins. Here we describe the functional analyses of the natural splice variants and of synthetic variants that comprise an altered N-terminus and/or a modified central globular domain. All natural splice variants of HLF6 and HLF7 display no detectable thrombin-inhibitory potency. In contrast, some synthetic variants effectively inhibit thrombin, even with tails as short as six amino acid residues in length. Our data indicate that size and composition of the C-terminal tail of hirudins and HLFs can vary in a great extent, yet the full protein may still retain the ability to inhibit thrombin.

Pharmacological Activities and Mechanisms of Hirudin and Its Derivatives - A Review.

Hirudin, an acidic polypeptide secreted by the salivary glands of Hirudo medicinalis (also known as "Shuizhi" in traditional Chinese medicine), is the strongest natural specific inhibitor of thrombin found so far. Hirudin has been demonstrated to possess potent anti-thrombotic effect in previous studies. Recently, increasing researches have focused on the anti-thrombotic activity of the derivatives of hirudin, mainly because these derivatives have stronger antithrombotic activity and lower bleeding risk. Additionally, various bioactivities of hirudin have been reported as well, including wound repair effect, anti-fibrosis effect, effect on diabetic complications, anti-tumor effect, anti-hyperuricemia effect, effect on cerebral hemorrhage, and others. Therefore, by collecting and summarizing publications from the recent two decades, the pharmacological activities, pharmacokinetics, novel preparations and derivatives, as well as toxicity of hirudin were systematically reviewed in this paper. In addition, the clinical application, the underlying mechanisms of pharmacological effects, the dose-effect relationship, and the development potential in new drug research of hirudin were discussed on the purpose of providing new ideas for application of hirudin in treating related diseases.

The efficacy and safety of Hirudin plus Aspirin versus Warfarin in the secondary prevention of Cardioembolic Stroke due to Nonvalvular Atrial Fibrillation: A multicenter prospective cohort study.

Background: To investigate the efficacy and safety of hirudin plus aspirin therapy compared with warfarin in the secondary prevention of cardioembolic stroke due to nonvalvular atrial fibrillation (NVAF). Methods: Patients with cardioembolic stroke due to NVAF were prospectively enrolled from 18 collaborating hospitals from Dec 2011 to June 2015. Fourteen days after stroke onset, eligible patients were assigned to the hirudin plus aspirin group (natural hirudin prescribed as the traditional Chinese medicine Maixuekang capsule, 0.75 g, three times daily, combined with aspirin 100 mg, once daily) or the warfarin group (dose-adjusted warfarin targeting international normalized ratio (INR) 2-3, with an initial daily dose of 1.25 mg). Patients were followed up at 1, 2, 3, 6, 9, and 12 months after stroke onset. Time in therapeutic range (TTR) was calculated according to Rosendaal methodology to evaluate the quality of INR management in the warfarin group. The primary efficacy endpoint was the recurrence of stroke within 12 months after stroke onset. Safety was assessed as the occurrence of the composite event "intracranial hemorrhage and other bleeding events, death, and other serious adverse events". The Cox proportional hazard model and Kaplan-Meier curve were used to analyze the efficacy and safety events. Results: A total of 221 patients entered final analysis with 112 patients in the hirudin plus aspirin group and 109 in the warfarin group. Over the whole duration of our study, TTR for patients taking warfarin was 66.5 % ± 21.5%. A significant difference was not observed in the recurrence of stroke between the two groups (3.57% vs. 2.75%; P = 0.728). The occurrence of safety events was significantly lower in the hirudin plus aspirin group (2.68% vs.10.09%; P = 0.024). The risk for efficacy event was similar between the two groups (hazard ratio (HR), 1.30; 95% confidence interval (CI), 0.29-5.80). The safety risk was significantly lower in the hirudin plus aspirin group (HR, 0.27; 95% CI, 0.07-0.95). Kaplan-Meier analysis revealed significant difference in the temporal distribution in safety events (P = 0.023) but not in stroke recurrence (P = 0.726). Conclusion: Significant difference in efficacy was not detected between warfarin group and hirudin plus aspirin group. Compared with warfarin, hirudin plus aspirin therapy had lower safety risk in the secondary prevention of cardioembolic stroke due to NVAF.

Artificial intelligence based identification of the functional role of hirudin in diabetic erectile dysfunction treatment.

Diabetic erectile dysfunction (DED) hugely affected the patients' sexual life quality. However, there are no satisfactory therapeutic methods and intervention targets for this subtype of erectile dysfunction (ED). Inspired by the clinical practice of traditional Chinese medicine (TCM), we found that hirudin, the main active ingredient in the leech, could ameliorate the ED symptoms of the DED mouse model. To further reveal the underlying mechanism of hirudin, we designed a novel strategy to discover potential targets based on the diagnostic system of TCM, and found that myeloperoxidase (MPO) was a promising target of hirudin. Hirudin directly interacts with MPO and inhibits its activity, thus further decreases the content of oxidized low-density lipoprotein (ox-LDL) in serum. Our results demonstrated that the hirudin could ameliorate the symptoms of DED, and revealed the underlying mechanism of hirudin in regulating the activity of MPO.

Effects of Time-Interval since Blood Draw and of Anticoagulation on Platelet Testing (Count, Indices and Impedance Aggregometry): A Systematic Study with Blood from Healthy Volunteers.

Platelet count, indices (mean volume, young-immature platelet fraction) and aggregation are widely used laboratory parameters to investigate primary hemostasis. We performed a systematic, thorough evaluation of the influence of the time-interval since blood draw from 20 healthy individuals and of the anticoagulation of collected blood on such parameters. Blood was anticoagulated with citrate, K2-ethylenediaminetetraacetic acid (EDTA) and hirudin and analyzed 5, 30, 60, 120 and 180 min after blood draw. Multiple electrode aggregometry (MEA) was performed with either hirudin (half-diluted with NaCl) or citrate samples (half-diluted with NaCl or CaCl2 3 mM). Platelet count and indices (Sysmex XN-20) were rather stable over time with EDTA blood. MEA results were lower with citrate blood than with hirudin blood; supplementation with calcium was partially compensatory. MEA results were also lower when performed less than 30 or more than 120 min after blood draw. Platelet clumping, quantitatively estimated with microscope examination of blood smears, was more important in hirudin blood than citrate or EDTA blood and could explain some of the differences observed between preanalytical variables. The results stress once more the importance of preanalytical variables in hemostasis laboratory testing. Decision thresholds based on those tests are only applicable within specific preanalytical conditions.

The hirudin-like factors HLF3 and HLF4-hidden hirudins of European medicinal leeches.

The hirudin-like factors 3 (HLF3) and 4 (HLF4) belong to a new class of leech-derived factors and are present in specimens of the three European medicinal leeches, Hirudo medicinalis, Hirudo verbana, and Hirudo orientalis, respectively. Here we describe the functional analysis of natural and synthetic variants of HLF3 and HLF4. Whereas the natural variants display only very low or no detectable anti-coagulatory activities, modifications within the N-termini in combination with an exchange of the central globular domain have the potency to greatly enhance the inhibitory effects of respective HLF3 and HLF4 variants on blood coagulation. Our results support previous observations on the crucial importance of all parts (both the N- and C-termini as well as the central globular domains) of hirudin and HLF molecules for thrombin inhibition.

European Medicinal Leeches-New Roles in Modern Medicine.

Before the advent of modern medicine, natural resources were widely used by indigenous populations for the prevention and treatment of diseases. The associated knowledge, collectively described as folk medicine or traditional medicine, was largely based on trial-and-error testing of plant extracts (herbal remedies) and the use of invertebrates, particularly medicinal maggots of the blowfly Lucilia sericata and blood-sucking leeches. The widespread use of traditional medicine in the West declined as scientific advances allowed reproducible testing under controlled conditions and gave rise to the modern fields of biomedical research and pharmacology. However, many drugs are still derived from natural resources, and interest in traditional medicine has been renewed by the ability of researchers to investigate the medical potential of diverse species by high-throughput screening. Likewise, researchers are starting to look again at the benefits of maggot and leech therapy, based on the hypothesis that the use of such animals in traditional medicine is likely to reflect the presence of specific bioactive molecules that can be developed as drug leads. In this review, we consider the modern medical benefits of European medicinal leeches based on the systematic screening of their salivary proteins.

Effects of Hirudin on High Glucose-Induced Oxidative Stress and Inflammatory Pathway in Rat Dorsal Root Ganglion Neurons.

OBJECTIVE: To investigate protective effects of hirudin on oxidative stress and apoptosis of spinal dorsal root ganglion cells in high-glucose rats at the cellular and molecular level. METHODS: Dorsal root ganglion neurons (DRGn) were harvested from embryonic day in 15 SD rats, purified and identificated after primary culture. They were divided into the normal control group, high-glucose (HG) group, positive control (alpha-lipoic acid, ALA) group, low-dose hirudin group (H1), medium-dose hirudin group (H2) and high-dose hirudin group (H3). The control group was cultured by neuron specific culture medium, while the HG group was cultured by neuron specific culture medium and 20 mmol/L glucose (HG medium). The hirudin groups were cultured by HG medium+0.25 IU/mL hirudin (H1), HG medium+0.5 IU/mL hirudin (H2) and HG medium+1 IU/mL hirudin (H3). The ALA group was cultured by HG medium+100 µ mol/L ALA. 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenylt etrazolium bromide (MTT) assay was used to explore the optimum concentration and intervention time. Flow cytometry assay was used to detect the level of reactive oxygen series (ROS). Western blot and quantificational realtime polymerase chain reaction (qRT-PCR) were used to detect the expression of protein and mRNA of nuclear factor erythroid 2-related factor 2 (Nrf-2), hemeoxygence-1 (HO-1), nuclear factor-κ B (NF-κ B) and Caspase-3. TUNEL assay was used to test the apoptosis rate of different groups. RESULTS: After 24 h of culture, the cell activity of hirudin and ALA groups were higher than that of HG group, and there was a statistical difference between the H1 group and HG group (P<0.05). In hirudin groups, the apoptosis rate of cells, the expression of activated Caspase-3 protein and Caspase-3 mRNA were lower than those of HG group (P<0.01), higher than those of ALA group (P<0.01 or P<0.05). The ROS level of hirudin groups was higher than that of ALA group (P<0.01), lower than that of HG group (P<0.01 or P<0.05). The expression of NF-κ B (P65) protein in H3 group were lower than those of HG group (P<0.05). The expression of Nrf-2 protein in hirudin groups was higher than that of HG group (P<0.01), lower than that of ALA group (P<0.01 or P<0.05). The expression of HO-1 protein in hirudin groups was lower than that of ALA group (P<0.01 or P<0.05), higher than that of HG group (P<0.01 or P<0.05). CONCLUSIONS: The activity of DRGn cells can be promoted by hirudin under HG conditions. The effects of hirudin on the inhibition of HG on DRGn cells damage mainly include scavenging ROS, up-regulating Nrf-2/HO-1 pathway, inhibiting activation of NF-κ B pathway, down-regulating the expression of and Caspase-3 and reducing DRGn cell apoptosis.

Hirudin improves renal interstitial fibrosis by reducing renal tubule injury and inflammation in unilateral ureteral obstruction (UUO) mice.

Renal interstitial fibrosis (RIF) often occurs in many chronic kidney diseases (CKD). Hirudin now is applied to treat fibrosis in some organs. In this study, we verified the treatment effects of hirudin on RIF in vivo and in vitro with the underlying mechanism. The RIF in vivo was the unilateral ureteral obstruction (UUO) model and RIF in vitro was the renal tubular epithelial cells induced by TGF-ß. The renal pathological changes and renal fibrosis were observed by hematoxylin and eosin (H&E) staining and Masson staining. The α-SMA in renal tissues was detected by immunohistochemistry. The inflammatory factors were analyzed by the ELISA assay. The cell apoptosis was observed by TUNEL assay. The related proteins of fibrosis, epithelial-mesenchymal transition (EMT) and apoptosis were assessed by western blot analysis. The experimental data demonstrated that hirudin decreased fibrosis, EMT, inflammation and cell apoptosis in renal tissues of UUO rats and TGF-ß-induced renal tubular epithelial cells. Furthermore, hirudin also reduced the expression of collgen-I, FN, α-SMA, N-cad, slug, E-cad, IL-1ß, IL-6 and TNF-α in mice serum and TGF-ß-induced renal tubular epithelial cells. The apoptosis related proteins (pro-caspase3, pro-caspase9, bcl2 and bax) expression was also down-regulated in renal tissues of UUO rats. In conclusion, hirudin depressed the fibrosis in renal tissues and renal tubular epithelial cells by inhibiting the inflammation, regulating the related proteins of fibrosis and ETM and decreasing the apoptosis of renal tubular epithelial cells. These findings may offer an effective treatment method for RIF.

Effect of hirudin on expressions of urate transporters OAT1, URAT1 and GLUT9 in hyperuricemia rats / 中草药

Objective: To explore the effect of hirudin on hyperuricemia rats and its mechanism. Methods: Male Wistar rats were randomly divided into control group, model group, allopurinol (30 mg/kg) group, hirudin low-, middle- and high-dose (0.2, 0.4, 0.8 g/kg) group. Rats were ig potassium oxonate (0.75 g/kg) to induce hyperglycemia model, once a day for five weeks. And all administration groups were respectively ig corresponding doses of drugs. The level of uric acid in serum and urine of rats were measured by biochemical method; The level of organic anion transporter 1 (OAT1) in kidney was measured by immunohistochemistry; The protein expressions of glucose transporter 9 (GLUT9), OAT1 and urate transporter 1 (URAT1) in kidney were measured by western blotting; The expression levels of GLUT9, OAT1 and URAT1 mRNA in kidney were detected by qRT-PCR. Results: Compared with control group, the level of uric acid in serum and urine of rats in model group was significantly increased (P < 0.01), the expressions of GLUT9, URAT1 mRNA and protein were significantly increased (P < 0.01), the expressions of OAT1 mRNA and protein were significantly decreased (P < 0.01). Compared with model group, the level of uric acid in serum and urine of rats in hirudin group were significantly decreased (P < 0.01), the expressions of GLUT9, URAT1 mRNA and protein were significantly reduced (P < 0.01), the expressions of OAT1 mRNA and protein were significantly increased (P < 0.01). Conclusion Hirudin can reduce the uric acid by regulating the expressions of renal urate transporters OAT1, URAT1 and GLUT9 in hyperuricemia rats.

Hirudin and Decorsins of the North American Medicinal Leech Macrobdella decora: Gene Structure Reveals Homology to Hirudins and Hirudin-like Factors of Eurasian Medicinal Leeches.

Blood-sucking leeches, some of which are referred to as medicinal leeches, have caught attention not only because of their medical purposes, but also as study organisms to conduct research within fields as diverse as neurobiology, osmoregulation, ecology, and phylogeny. Of particular interest is the question whether hemophagy in leeches is of single origin or evolved independently several times. A key component in the saliva of hematophagous leeches is hirudin, a strong natural inhibitor of thrombin and hence the blood coagulation cascade. Multiple isoforms of hirudin have been described within and among several leech species and genera, often based on sequence data only. The identification of hirudin-like factors (HLFs) illustrated the necessity to underpin such predictions by functional tests. We overexpressed and purified the hirudin of the North American medicinal leech, Macrobdella decora, and proved its thrombin-inhibiting activity. In addition, analysis of the gene structure of both hirudin and some of the decorsins of M. decora clearly indicated conserved exon and intron positions when compared to genes of hirudins and HLFs of Eurasian medicinal leeches. Our data provide evidence for the incorporation of decorsins into the hirudin superfamily and support the concept of a single origin of blood feeding in jawed leeches.

The effects of a hirudin/liposome complex on a diabetic nephropathy rat model.

BACKGROUND: Hirudin, an extract from Hirudo spp., is an anticoagulant used to treat a variety of renal diseases, including diabetic nephropathy (DN). Currently, hirudin has to be used at high dosages to treat DN because it poorly targets the kidneys, although at high dosages it can have severe side effects. Developing a targeted drug delivery system for hirudin, then, could boost its positive therapeutic effects while lowering the risk of side effects. Liposomes have been demonstrated to have significant renal targeting potential, but here we show that a hirudin-loaded liposome is an effective delivery method for patients with DN. METHOD: In this study, we prepared a hirudin/liposome complex and tested its efficacy by injecting it into a rat model. We then compared the renal accumulation of hirudin between complex-injected rat models and rat models that received injections of hirudin alone. We also investigated the mechanisms behind the complex's effects. RESULT: The hirudin/liposome complex increased the accumulation of hirudin in kidney tissues and relieved the renal injury in DN rat models. Moreover, the hirudin/liposome complex down-regulated the expression of TGF-ß1 and VEGF in the kidneys. CONCLUSION: We demonstrated that a hirudin/liposome complex can have a significant positive effect on DN. The mechanism may be that the complex inhibits the expression of VEGF and TGF-ß1.