Effects of environmental factors and intraspecific niche overlap on the body and ecological characteristics of red-tongued pit vipers (Gloydius ussuriensis).

The body condition of a snake species provides important physiological, morphological, and ecological information that elucidates its habits, life cycle, and competitive relationships. We measured the body size and condition of the wild Gloydius ussuriensis population in South Korea from 2018 to 2022, analyzed the degree of intraspecific niche overlap, and identified the geographic and climatic factors affecting their body condition. We found that the females were longer than the males. The body condition index (BCI) of G. ussuriensis differed depending on sex and season; the BCI of the females and males was highest in August and October, respectively. Environmental factors related to altitude and temperature affected the body condition of G. ussuriensis; BCI increased as the mean annual temperature and winter temperature increased; however, it increased when the annual temperature range decreased. The mean Pinaka index was 0.96, indicating a high degree of niche overlap; however, the niche overlap among the neonates was less than that among the adults and juveniles. To elucidate the causes of niche overlap and mechanisms behind the intraspecific competition among G. ussuriensis individuals, the habitat and utilization of food resources at different development stages of G. ussuriensis should be further investigated.

TAPEWORMS (CESTODA: OPHIOTAENIA) FROM THE NORTHERN COTTONMOUTH (AGKISTRODON PISCIVORUS).

The northern cottonmouth, Agkistrodon piscivorus (Lacépède, 1789) (Viperidae: Crotalinae), occurs in the southeastern United States and is one of the few semiaquatic vipers in the world. Three proteocephalid tapeworms of the genus OphiotaeniaLa Rue, 1911 (Cestoda), have been described from this venomous snake. A critical evaluation of type specimens and tapeworms recently collected from A. piscivorus has revealed that only 2 species, Ophiotaenia marenzelleri (Barrois, 1898) and Ophiotaenia grandisLa Rue, 1911 (new synonym Ophiotaenia agkistrodontis [Harwood, 1933]), are specific parasites of this crotaline viper; both species are redescribed here. Ophiotaenia grandis was originally described from a mixture of 2 species: 'true' O. grandis, which is indistinguishable from O. agkistrodontis described 22 yr later and thus considered to be a junior synonym of O. grandis, and O. marenzelleri. Ophiotaenia marenzelleri, also reported from the pygmy rattlesnake, Sistrurus miliarius (Linnaeus, 1766), is a larger tapeworm with a massive scolex, a large cirrus sac, a very large, annular vaginal sphincter near the equatorial gonopore, and an oval, 3-layered embryophore surrounded by a nearly square hyaline outer membrane. Ophiotaenia grandis is much smaller and more slender and has a narrower scolex, a smaller cirrus sac and vaginal sphincter, a 2-layered embryophore, and a distinctly pre-equatorial gonopore. In addition to O. marenzelleri and O. grandis, other Ophiotaenia species typical of semiaquatic snakes (Colubridae: Natricinae) may be present in the northern cottonmouth, which serves only as a postcyclic or occasional host. There is also a tabular summary of 18 species of Ophiotaenia from semiaquatic snakes worldwide, with information on their hosts, distribution, and taxonomically important characters, including key measurements.

Safe administration of Crotalidae equine immune F(ab')2 antivenom in a patient who suffered anaphylaxis from Crotalidae polyvalent immune Fab antivenom.

Allergic reactions to Crotalidae polyvalent immune Fab and Crotalidae immune F(ab')2 are uncommon but potentially life-threatening. It is unknown whether cross-reactivity reactions exist between these two antivenoms. We report a case of a patient who suffered anaphylaxis from Crotalidae polyvalent immune Fab but subsequently was safely administered Crotalidae immune F(ab')2 after a presumed Agkistrodon contortix (copperhead) envenomation. This single case supports the safety of Crotalidae immune F(ab')2 administration in patients with a history of anaphylaxis to Crotalidae polyvalent immune Fab treatment.

De Novo Venom Gland Transcriptome Assembly and Characterization for Calloselasma rhodostoma (Kuhl, 1824), the Malayan Pit Viper from Malaysia: Unravelling Toxin Gene Diversity in a Medically Important Basal Crotaline.

In Southeast Asia, the Malayan Pit Viper (Calloselasma rhodostoma) is a venomous snake species of medical importance and bioprospecting potential. To unveil the diversity of its toxin genes, this study de novo assembled and analyzed the venom gland transcriptome of C. rhodostoma from Malaysia. The expression of toxin genes dominates the gland transcriptome by 53.78% of total transcript abundance (based on overall FPKM, Fragments Per Kilobase Million), in which 92 non-redundant transcripts belonging to 16 toxin families were identified. Snake venom metalloproteinase (SVMP, PI > PII > PIII) is the most dominant family (37.84% of all toxin FPKM), followed by phospholipase A2 (29.02%), bradykinin/angiotensin-converting enzyme inhibitor-C-type natriuretic peptide (16.30%), C-type lectin (CTL, 10.01%), snake venom serine protease (SVSP, 2.81%), L-amino acid oxidase (2.25%), and others (1.78%). The expressions of SVMP, CTL, and SVSP correlate with hemorrhagic, anti-platelet, and coagulopathic effects in envenoming. The SVMP metalloproteinase domains encode hemorrhagins (kistomin and rhodostoxin), while disintegrin (rhodostomin from P-II) acts by inhibiting platelet aggregation. CTL gene homologues uncovered include rhodocytin (platelet aggregators) and rhodocetin (platelet inhibitors), which contribute to thrombocytopenia and platelet dysfunction. The major SVSP is a thrombin-like enzyme (an ancrod homolog) responsible for defibrination in consumptive coagulopathy. The findings provide insight into the venom complexity of C. rhodostoma and the pathophysiology of envenoming.

Stimulation of platelet aggregation by affinity captured rhodocytin from the Malayan pit viper Calloselasma rhodostoma.

The receptor protein CLEC-2 on platelet membranes is the target of the endogenous ligand podoplanin found on cancer cells and of rhodocytin, a snake venom component of the Malayan pit viper Calloselasma rhodostoma. Ligand binding results in platelet activation, increased blood coagulation and thrombosis. In an effort to isolate rhodocytin, we have purified CLEC-2 as bait from E. coli. Affinity captured rhodocytin interacted with mammalian CLEC-2 and stimulated platelet aggregation in a dose dependent manner.

Upper Extremity Crotalid Envenomation: A Review of Incidence and Recent Trends in Management of Snakebites.

PURPOSE: The goal of this study was to evaluate the recent trends in the management of upper extremity Crotalid envenomation in the state of Georgia, United States. METHODS: A retrospective review of the Georgia Poison Center database looking at the reported snakebites to the upper extremity between 2015 and 2020 was performed. Patient demographics, timing and location of injury, severity of envenomation, treatment, including use of antivenin and surgical intervention, and reported complications related to the use of antivenin was extracted. RESULTS: A retrospective review of snakebites between 2015 and 2020 showed 2408 snakebite cases with a mean patient age of 37.4 years. Males incurred 62.8% of all bites. The highest incidence was in summer 52.5%, and between the hours of 5 PM to midnight 57.2%. Overall, 1010 (41.9%) of all bites were categorized as venomous snakebites (55.6% copperhead, 20% rattlesnake, 2.4% cottonmouth, and 22% miscellaneous [including 3 Elapid envenomations] or unidentified. The total number of venomous bites to the upper extremity was 575 (56.9%) and 567 patients received antivenin. Envenomation severity was mild in 29%, moderate in 45%, severe in 10%, and undetermined in 16% of cases. Crotalidae polyvalent immune Fab (Ovine) was the main antivenin used, with overall mean initial therapy dose of 6.2 vials and 59% of patients receiving maintenance therapy. Three patients (0.5%) had a severe anaphylactic reaction to antivenin requiring cessation of therapy. Seven patients had acute compartment syndrome of the upper extremity requiring fasciotomy (3 copperhead, 2 rattlesnake, and 2 unidentified). There was no reported mortality during this period. CONCLUSIONS: Hand surgeons should be familiar with the management of upper extremity Crotalid envenomation. Antivenin remains the main treatment for symptomatic patients. Crotalid snakebites rarely require operative intervention. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Epidemiology and Characteristics of North American Crotalid Bites Reported to the National Poison Data System 2006-2020.

OBJECTIVES: North American pit viper, or crotalid bites, remain a low-incidence and potentially high-consequence medical event. Although the venom of these snakes is known to cause tissue, hematologic, and neurologic toxicity, the published literature on North American crotalid bites remains limited. The National Poison Data System, the data repository for the 55 poison control centers in the United States, offers a unique opportunity to examine nationwide trends involving venomous snake bites. METHODS: National Poison Data System cases involving North American crotalids from 2006 to 2020 were analyzed. Data collected included age and type of snake, date, geographic location, pertinent clinical characteristics, treatments administered, and medical outcomes including incidence of "dry" bites and death. RESULTS: A total of 55,914 cases were identified during the 15-year study period. Cases, especially those involving copperheads, increased during the study period. Most of the cases were reported in July. Cases were reported in all 50 states and Washington, DC, with Texas having the most cases (n = 9115). North Carolina had the largest increase in bites during the study period. Moderate or major medical outcomes were documented in 58% (n = 32,584) of cases, with 25% (n = 14,195) being admitted to a critical care unit. Puncture wound, edema, and pain were the most commonly documented symptoms. Antivenom was documented as being administered in 25% (n = 14,151) of cases. Dry bites were reported in <1.5% of cases. Thirty-two deaths were reported, 23 involving rattlesnakes. CONCLUSIONS: This study demonstrates that reported North American crotalid bites appear to be increasing over time and are associated with potentially significant morbidity. Mortality, however, remains low.

Platelet Desialylation Is a Novel Mechanism and Therapeutic Target in Daboia siamensis and Agkistrodon halys Envenomation-Induced Thrombocytopenia.

Venom-induced thrombocytopenia (VIT) is one of the most important hemotoxic effects of a snakebite, which is often associated with venom-induced consumptive coagulopathy (VICC). Refractory thrombocytopenia without significant coagulation abnormalities has also been reported after envenomation by some viperid snakes; however, the mechanisms are not well understood and therapeutic strategies are lacking. Here, we found that patients injured by Daboia siamensis or Agkistrodon halys snakes, who were resistant to standard antivenom treatment, had developed coagulopathy-independent thrombocytopenia. Venoms from these viperid snakes, rather than from the elapid snake (Bungarus multicinctus), induced platelet surface expression of neuraminidase-1 (NEU-1), and significantly increased the desialylation of the glycoproteins on human platelets. The desialylated platelets caused by viperid snake venoms were further internalized by macrophages, which resulted in reduced platelet numbers in peripheral blood. Importantly, neuraminidase inhibitor significantly decreased viper venom-induced platelet desialylation, therefore inhibiting platelet phagocytosis by macrophages, and alleviating venom-induced thrombocytopenia. Collectively, these findings support an important role for desialylated platelet clearance in the progression of viper envenomation-induced, coagulopathy-independent thrombocytopenia. Our study demonstrates that the neuraminidase inhibitor may be a potential therapy or adjuvant therapy to treat snakebite-induced thrombocytopenia.

Histopathological Changes in the Liver, Heart and Kidneys Following Malayan Pit Viper (Calloselasma rhodostoma) Envenoming and the Neutralising Effects of Hemato Polyvalent Snake Antivenom.

Calloselasma rhodostoma (Malayan pit viper) is a medically important snake species that is widely distributed across Southeast Asia. Systemic coagulopathy causing severe haemorrhage and local tissue injury is commonly observed following C. rhodostoma envenoming. However, nephrotoxicity and congestive heart failure were previously reported in a patient who had a long length of hospital stay. In this study, we determined the effect of C. rhodostoma envenoming on cardiovascular disturbances and the associated morphological changes in the liver, heart and kidneys using animal models. We also evaluated the efficacy of Hemato polyvalent antivenom (HPAV; Queen Saovabha Memorial Institute (QSMI) of the Thai Red Cross Society, Thailand) in neutralising the histopathological effects of C. rhodostoma venom. The intravenous (i.v.) administration of C. rhodostoma venom (1000 µg/kg) caused a rapid decrease in mean arterial pressure (MAP) followed by complete cardiac collapse in anaesthetized rats. Moreover, the intraperitoneal (i.p.) administration of C. rhodostoma venom (11.1 mg/kg; 3 × LD50) for 24 h caused cellular lesions in the liver and heart tissues. C. rhodostoma venom also induced nephrotoxicity, as indicated by the presence of tubular injury, interstitial vascular congestion and inflammatory infiltration in the whole area of the kidney. The administration of HPAV, at manufacturer-recommended doses, 15 min prior to or after the addition of C. rhodostoma venom reduced the extent of the morphological changes in the liver, heart and kidneys. This study found that experimental C. rhodostoma envenoming induced cardiovascular disturbances, hepatotoxicity and nephrotoxicity. We also highlighted the potential broad utility of HPAV to neutralise the histopathological effects of C. rhodostoma venom. The early delivery of antivenom appears capable of preventing envenoming outcomes.

Intraspecific investigation of dehydration-enhanced innate immune performance and endocrine stress response to sublethal dehydration in a semi-aquatic species of pit viper.

Sublethal dehydration can cause negative physiological effects, but recent studies investigating the sub-lethal effects of dehydration on innate immune performance in reptiles have found a positive correlation between innate immune response and plasma osmolality. To investigate whether this is an adaptive trait that evolved in response to dehydration in populations inhabiting water-scarce environments, we sampled free-ranging cottonmouth snakes (n=26 adult cottonmouths) from two populations inhabiting contrasting environments in terms of water availability: Snake Key (n=12), an island with no permanent sources of fresh water, and Paynes Prairie (n=14), a flooded freshwater prairie. In addition to field surveys, we manipulated the hydration state of 17 cottonmouths (Paynes Prairie n=9, Snake Key n=8) in a laboratory setting and measured the response of corticosterone and innate immune performance to dehydration with the aim of identifying any correlation or trade-offs between them. We measured corticosterone of cottonmouths at a baseline level and then again following a 60 min stress test when at three hydration states: hydrated, dehydrated and rehydrated. We found that innate immune performance improved with dehydration and then returned to baseline levels within 48 h of rehydration, which agrees with previous research in reptiles. Despite the frequent exposure of cottonmouths on Snake Key to dehydrating conditions, we did not find cottonmouths inhabiting the island to show a greater magnitude or more prolonged immune response compared with cottonmouths from Paynes Prairie. We also found a positive association between dehydration and corticosterone values.

Using Haemocoagulase Agkistrodon in Patients Undergoing Transurethral Plasmakinetic Resection of the Prostate: A Pilot, Real-World, and Propensity Score-Matched Study.

Objectives: To compare the clinical outcomes of using different hemostatic agents after transurethral plasmakinetic resection of the prostate (TUPKP) in benign prostatic hyperplasia (BPH) patients. Methods: The patients were divided into 5 groups according to the hemostatic agents used after TUPKP, including the haemocoagulase agkistrodon for injection (HCA), hemocoagulase for injection (HC), hemocoagulase bothrops atrox for injection (HCB), ethylenediamine diaceturate injection (EDD), and tranexamic acid (TXA). Propensity score matching was performed based on age, body mass index, prostate volume, hypertension status, fasting blood glucose, smoking, and drinking history. The hospitalization time, bladder irrigation time, indwelling catheterization time, the patency of urine flow, and blood transfusion records were used as outcome indicators to compare the clinical effects of these five agents. Results: We finally matched 65 pairs receiving HCA or HC, 71 pairs receiving HCA or HCB, 38 pairs receiving HCA or TXA, and 29 pairs receiving HCA or EDD. Compared with HC, HCA given during the perioperative period significantly reduced the median hospitalization time [7.00 days (5.00, 8.00) vs. 9.00 days (8.00, 10.00); p < 0.001] and median catheterization time (109.00 hours [88.00, 129.00] vs. 164.00 hours [114.00, 189.00], p < 0.001). Compared with EDD, the median hospitalization time (7.00 days [6.00, 8.00] vs. 10.00 days [8.00, 11.00]; p < 0.001) and median catheterization time (113.00 hours [95.00, 143.00] vs. 160.00 hours [139.00, 168.00]; p < 0.001) were also significant shorter in HCA group. Compared with HCB, median bladder irrigation time (45.00 hours [27.00, 71.00] vs. 49.00 hours [45.00, 72.00]; p = 0.04) was shorter in the HCA group. However, there were no statistical differences in outcomes between HCA and TXA. Conclusions: HCA probably has an advantage over HC, HCB, and EDD in reducing the hospitalization time, catheterization time, and bladder irrigation time among BPH patients undergoing TUPKP.

Coagulopathy following Crotaliπae snakebites in northeast Florida.

Effects of Crotalinae envenomation vary by geographical areas and research into coagulopathy and effects of antivenom are needed to optimize management. This was a single-center retrospective review with testing on presentation and 4 h after; antivenom administration was noted and data analyzed overall and comparing envenomations. One hundred and nineteen snakebites evaluated with 59 identified as Crotalinae and half receiving antivenom. PT/aPTT was elevated in 20% of water moccasin/copperhead and 21% of rattlesnake bites. DIC-like syndrome occurred in 8% water moccasin/copperhead and 6% rattlesnake bites. Antivenom did not seem to correct PT or aPTT at 4 h follow-up in most cases. Thrombotic microangiopathy was not seen. Coagulopathy was prevalent affecting one in five patients in this cohort and does seem to persist at short interval follow-up, even in those receiving antivenom. We support guidelines recommending clinical monitoring and serial coagulation profiles in such cases. Blood Coagul Fibrinolysis 30:000 - 000 Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.

[Agkistrodon halys venom antitumor component-I inhibits vasculogenic mimicry in triple-negative breast cancer cells in vitro by down-regulating MMP2].

OBJECTIVE: To investigate the inhibitory effect of agkistrodon halys venom antitumor component-I (AHVAC-I) on vasculogenic mimicry (VM) formation in triple-negative breast cancer MDA-MB-231 cells and explore its possible mechanism. METHODS: CCK8 assay was used to determine the optimal concentration of AHVAC-I for cell treatment based on its halfinhibitory concentration (IC50). MDA-MB-231 cells were treated with different concentrations of AHVAC-I or 5-Fu, and the changes in vasomimetic capacity of the cells were examined using Matrigel assay. The expression levels of matrix metalloproteinase-2 (MMP2) and MMP9 in the treated cells were detected using quantitative PCR and Western blotting. RESULTS: Compared with the control treatment with culture medium, treatment with 5, 10 and 20 µg/mL AHVAC-I significantly reduced vasomimetic ability of MDA-MB-231 cells in a dose-dependent manner (P < 0.01). MMP2 supplementation obviously restored the vasomimetic ability of the cells inhibited by AHVAC-I. CONCLUSION: AHVAC-I inhibits VM formation in triplenegative breast cancer cells in vitro by down-regulating MMP2 production.

Effect of Agkistrodon halys antivenom in patients bit by green pit viper and the prognostic role of the disease - a retrospective cohort study.

BACKGROUND AND AIMS: In Mainland China and Hong Kong, health authorities utilize Agkistrodon halys antivenom in the treatment of patients who sustained bites from green pit vipers. However, the treatment benefit of Agkistrodon halys antivenom among such patients is still controversial. The purpose of this study is to evaluate the coagulation parameters normalization time of Agkistrodon halys antivenom in patients who sustained green pit viper bites and explore independent risk factors of patient prognosis. METHODS: Data were extracted from the Donghua Hospital Information System. Comparison of the two groups of patients - who used antivenom (GPUA) and who did not use antivenom (GPNUA) were performed using stratified analysis, univariate and multivariate ordered logistic regression models to evaluate the coagulation parameters normalization time. Univariate and multivariate ordered logistic regression models were used to explore independent risk factors of patient prognosis. RESULTS: Between the GPUA and GPNUA groups, there is no significant difference in the coagulation parameters normalization time with the treatment of Agkistrodon halys antivenom. GPNUA consumed more cryoprecipitate and platelets and had a lower cost. The patient's severity of the bite, first coagulation profile, and dosages of fresh frozen plasma, platelet, and red cell suspension was found to be risk factors for the normalization time of coagulation parameters. CONCLUSIONS: The therapeutic effect of Agkistrodon halys antivenom in green pit vipers bite patients is not quite satisfying. In addition, more attention should be paid to the first coagulation profile, blood clotting factors indices, platelet count (PLT), and hemoglobin when treating such patients.

Predictors of FabAV use in copperhead envenomation.

CONTEXT: Crotaline snake envenomation is a serious medical condition affecting thousands of Americans each year. Variation in the treatment of Crotaline snakebites exists among physicians in the United States. Management of copperhead snakebites is controversial with some experts advocating minimal intervention, rarely necessitating antivenom use and, even more rarely, surgical intervention. This study assessed the use of Crotaline Polyvalent Immune Fab antivenom (Ovine) (FabAV) and explored factors influencing the decision to prescribe antivenom for copperhead envenomation in patients in Northeastern Oklahoma. METHODS: A retrospective cohort study examining electronic medical records of patients with copperhead snakebites from July 1, 2014 to August 31, 2019. Data collected included: patient demographics, transfer information, snake species, bite site, progression of local tissue effects, additional clinical and lab results, patient comorbidities, and treatment strategy. Associations between patient variables and treatment were evaluated using the chi-square test of independence, median test, and logistic regression analysis. Associations were statistically significant if p < 0.05. DISCUSSION: Of the 130 patients bitten by a copperhead, a majority (75%) received FabAV. Symptoms of copperhead envenomation were mostly limited to the progression of tissue damage. Predictors of treatment with FabAV included progression of venom effects across major joints, younger age, comorbidities, and upper extremity bites. CONCLUSIONS: Patients who have multiple comorbidities, upper extremity bites and progression of venom effects across major joints are more likely to be treated with FabAV. The high usage of FabAV at the study site underscores the need for continued work to optimize the use of antivenom for copperhead envenomations.

Crotalidae Polyvalent Immune Fab and Cost-Effective Management of Hospital Admissions for Snakebites.

BACKGROUND: Venomous snakebites are a common clinical scenario in the Southeastern United States. CroFab® (Crotalidae Polyvalent Immune Fab (Ovine), BTG, Wales, UK) antivenom is indicated in cases involving pit vipers and is known to be expensive. The treatment protocol for snakebites is based on clinically subjective measures triggering the application, or escalation of, antivenom administration. The purpose of this study is to characterize the use of CroFab at our institution and to evaluate the impact of its use regarding cost and overall outcomes. We suspect that it is often used but potentially less often needed. We hypothesized that CroFab use was associated with increased length of stay (LOS) without an observed difference in patient outcomes. MATERIALS AND METHODS: A retrospective chart review of snakebite patients at our level-1 trauma center from 2000 to 2016 was performed. Snakebite location, snake species, number of vials of CroFab administered, hospital LOS, intensive care unit (ICU) LOS, and complications were identified for each patient. Patients were divided into CroFab (C) and no CroFab (NC) groups. RESULTS: One hundred ninety patients with venomous snakebites were included. 53.7% of patients received CroFab. There was no difference in the complication rate of C versus NC groups, (P = .1118). CroFab use was associated with longer hospital LOS (P < .0001) and ICU LOS (P < .0001). DISCUSSION: CroFab use was associated with increased LOS in our patient population. There was no difference in observed outcomes between the C and NC groups. These findings imply that CroFab is potentially over-used in our patient population.

Control of venom-induced tissue injury in copperhead snakebite patients: a post hoc sub-group analysis of a clinical trial comparing F(ab')2 to Fab antivenom.

INTRODUCTION: Fab antivenom (FabAV) halts progression of tissue injury and improves recovery in copperhead snakebite. It is unknown if F(ab')2AV does as well. The objective of this study was to compare control of tissue injury in copperhead snakebite patients treated with F(ab')2AV versus FabAV. METHODS: We performed a post hoc analysis of copperhead envenomated patients in a clinical trial comparing F(ab')2AV to FabAV. The outcomes for this analysis are the number of repeat doses required to obtain initial control, the number of patients requiring unscheduled doses during maintenance, and the time from antivenom administration to initial control. RESULTS: Twenty-one (13 F(ab')2AV, 8 FabAV) were copperhead patients. Median age was 46 years with a male predominance. Baseline severity was similar. One (8%) F(ab')2AV and 2(25%) FabAV patients required repeat initial dosing, difference = 17%, (95%CI -18, 57%). One (8%) F(ab')2AV and 1(13%) FabAV patients required additional doses after maintenance, difference = 5%, (95%CI -27, 45%). Median time to initial control was 2.7 range (2.0, 9.3) hours and 3.5 range (2.0, 7.4) for F(ab')2AV and FabAV respectively, difference -0.8 h (95% CI -2.6, 0.9). CONCLUSIONS: This exploratory analysis suggests that the available measures of the control of venom-induced tissue injury are similar between antivenom subgroups.

Agkistrodon halys venom antitumor component-I inhibits vasculogenic mimicry in triple-negative breast cancer cells in vitro by down-regulating MMP2 / 南方医科大学学报

OBJECTIVE@#To investigate the inhibitory effect of agkistrodon halys venom antitumor component-I (AHVAC-I) on vasculogenic mimicry (VM) formation in triple-negative breast cancer MDA-MB-231 cells and explore its possible mechanism.@*METHODS@#CCK8 assay was used to determine the optimal concentration of AHVAC-I for cell treatment based on its halfinhibitory concentration (IC50). MDA-MB-231 cells were treated with different concentrations of AHVAC-I or 5-Fu, and the changes in vasomimetic capacity of the cells were examined using Matrigel assay. The expression levels of matrix metalloproteinase-2 (MMP2) and MMP9 in the treated cells were detected using quantitative PCR and Western blotting.@*RESULTS@#Compared with the control treatment with culture medium, treatment with 5, 10 and 20 μg/mL AHVAC-I significantly reduced vasomimetic ability of MDA-MB-231 cells in a dose-dependent manner (P < 0.01). MMP2 supplementation obviously restored the vasomimetic ability of the cells inhibited by AHVAC-I.@*CONCLUSION@#AHVAC-I inhibits VM formation in triplenegative breast cancer cells in vitro by down-regulating MMP2 production.