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1.
Bioessays ; 46(1): e2300143, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37985957

RESUMO

Modeling metastasis in animal systems has been an important focus for developing cancer therapeutics. Xenopus laevis is a well-established model, known for its use in identifying genetic mechanisms underlying diseases and disorders in humans. Prior literature has suggested that the drug, ivermectin, can be used in Xenopus to induce melanocytes to convert into a metastatic melanoma-like state, and thus could be ideal for testing possible melanoma therapies in vivo. However, there are notable inconsistencies between ivermectin studies in Xenopus and the application of ivermectin in mammalian systems, that are relevant to cancer and melanoma research. In this review, we examine the ivermectin-induced phenotypes in Xenopus, and we explore the current uses of ivermectin in human research. We conclude that while ivermectin may be a useful drug for many biomedical purposes, it is not ideal to induce a metastatic melanocyte phenotype in Xenopus for testing the effects of potential melanoma therapeutics.


Assuntos
Melanoma , Animais , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Xenopus laevis , Ivermectina/farmacologia , Melanócitos/patologia , Mamíferos
2.
Clin Infect Dis ; 78(Supplement_2): S138-S145, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662693

RESUMO

BACKGROUND: Concerns that annual mass administration of ivermectin, the predominant strategy for onchocerciasis control and elimination, may not lead to elimination of parasite transmission (EoT) in all endemic areas have increased interest in alternative treatment strategies. One such strategy is moxidectin. We performed an updated economic assessment of moxidectin- relative to ivermectin-based strategies. METHODS: We investigated annual and biannual community-directed treatment with ivermectin (aCDTI, bCDTI) and moxidectin (aCDTM, bCDTM) with minimal or enhanced coverage (65% or 80% of total population taking the drug, respectively) in intervention-naive areas with 30%, 50%, or 70% microfilarial baseline prevalence (representative of hypo-, meso-, and hyperendemic areas). We compared programmatic delivery costs for the number of treatments achieving 90% probability of EoT (EoT90), calculated with the individual-based stochastic transmission model EPIONCHO-IBM. We used the costs for 40 years of program delivery when EoT90 was not reached earlier. The delivery costs do not include drug costs. RESULTS: aCDTM and bCDTM achieved EoT90 with lower programmatic delivery costs than aCDTI with 1 exception: aCDTM with minimal coverage did not achieve EoT90 in hyperendemic areas within 40 years. With minimal coverage, bCDTI delivery costs as much or more than aCDTM and bCDTM. With enhanced coverage, programmatic delivery costs for aCDTM and bCDTM were lower than for aCDTI and bCDTI. CONCLUSIONS: Moxidectin-based strategies could accelerate progress toward EoT and reduce programmatic delivery costs compared with ivermectin-based strategies. The costs of moxidectin to national programs are needed to quantify whether delivery cost reductions will translate into overall program cost reduction.


Assuntos
Ivermectina , Macrolídeos , Oncocercose , Macrolídeos/uso terapêutico , Macrolídeos/economia , Macrolídeos/administração & dosagem , Oncocercose/tratamento farmacológico , Oncocercose/prevenção & controle , Oncocercose/economia , Oncocercose/epidemiologia , Humanos , Ivermectina/economia , Ivermectina/uso terapêutico , Ivermectina/administração & dosagem , Administração Massiva de Medicamentos/economia , Erradicação de Doenças/economia , Análise Custo-Benefício
3.
Clin Infect Dis ; 78(Supplement_2): S93-S100, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662701

RESUMO

BACKGROUND: Mass drug administration (MDA) is the cornerstone for the elimination of lymphatic filariasis (LF). The proportion of the population that is never treated (NT) is a crucial determinant of whether this goal is achieved within reasonable time frames. METHODS: Using 2 individual-based stochastic LF transmission models, we assess the maximum permissible level of NT for which the 1% microfilaremia (mf) prevalence threshold can be achieved (with 90% probability) within 10 years under different scenarios of annual MDA coverage, drug combination and transmission setting. RESULTS: For Anopheles-transmission settings, we find that treating 80% of the eligible population annually with ivermectin + albendazole (IA) can achieve the 1% mf prevalence threshold within 10 years of annual treatment when baseline mf prevalence is 10%, as long as NT <10%. Higher proportions of NT are acceptable when more efficacious treatment regimens are used. For Culex-transmission settings with a low (5%) baseline mf prevalence and diethylcarbamazine + albendazole (DA) or ivermectin + diethylcarbamazine + albendazole (IDA) treatment, elimination can be reached if treatment coverage among eligibles is 80% or higher. For 10% baseline mf prevalence, the target can be achieved when the annual coverage is 80% and NT ≤15%. Higher infection prevalence or levels of NT would make achieving the target more difficult. CONCLUSIONS: The proportion of people never treated in MDA programmes for LF can strongly influence the achievement of elimination and the impact of NT is greater in high transmission areas. This study provides a starting point for further development of criteria for the evaluation of NT.


Assuntos
Albendazol , Filariose Linfática , Filaricidas , Ivermectina , Administração Massiva de Medicamentos , Filariose Linfática/tratamento farmacológico , Filariose Linfática/prevenção & controle , Filariose Linfática/epidemiologia , Filariose Linfática/transmissão , Humanos , Animais , Filaricidas/uso terapêutico , Filaricidas/administração & dosagem , Albendazol/administração & dosagem , Albendazol/uso terapêutico , Ivermectina/administração & dosagem , Ivermectina/uso terapêutico , Prevalência , Anopheles/parasitologia , Erradicação de Doenças/métodos , Wuchereria bancrofti/efeitos dos fármacos , Dietilcarbamazina/administração & dosagem , Dietilcarbamazina/uso terapêutico , Quimioterapia Combinada
4.
Antimicrob Agents Chemother ; : e0018124, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742896

RESUMO

Ivermectin (IVM) could be used for malaria control as treated individuals are lethal to blood-feeding Anopheles, resulting in reduced transmission. Tafenoquine (TQ) is used to clear the liver reservoir of Plasmodium vivax and as a prophylactic treatment in high-risk populations. It has been suggested to use ivermectin and tafenoquine in combination, but the safety of these drugs in combination has not been evaluated. Early derivatives of 8-aminoquinolones (8-AQ) were neurotoxic, and ivermectin is an inhibitor of the P-glycoprotein (P-gp) blood brain barrier (BBB) transporter. Thus, there is concern that co-administration of these drugs could be neurotoxic. This study aimed to evaluate the safety and pharmacokinetic interaction of tafenoquine, ivermectin, and chloroquine (CQ) in Rhesus macaques. No clinical, biochemistry, or hematological outcomes of concern were observed. The Cambridge Neuropsychological Test Automated Battery (CANTAB) was employed to assess potential neurological deficits following drug administration. Some impairment was observed with tafenoquine alone and in the same monkeys with subsequent co-administrations. Co-administration of chloroquine and tafenoquine resulted in increased plasma exposure to tafenoquine. Urine concentrations of the 5,6 orthoquinone TQ metabolite were increased with co-administration of tafenoquine and ivermectin. There was an increase in ivermectin plasma exposure when co-administered with chloroquine. No interaction of tafenoquine on ivermectin was observed in vitro. Chloroquine and trace levels of ivermectin, but not tafenoquine, were observed in the cerebrospinal fluid. The 3''-O-demethyl ivermectin metabolite was observed in macaque plasma but not in urine or cerebrospinal fluid. Overall, the combination of ivermectin, tafenoquine, and chloroquine did not have clinical, neurological, or pharmacological interactions of concern in macaques; therefore, this combination could be considered for evaluation in human trials.

5.
Antimicrob Agents Chemother ; : e0127223, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904389

RESUMO

Ivermectin, a broad-spectrum anti-parasitic drug, has been proposed as a novel vector control tool to reduce malaria transmission by mass drug administration. Ivermectin and some metabolites have mosquito-lethal effect, reducing Anopheles mosquito survival. Ivermectin inhibits liver stage development in a rodent malaria model, but no inhibition was observed in a primate malaria model or in a human malaria challenge trial. In the liver, cytochrome P450 3A4 and 3A5 enzymes metabolize ivermectin, which may impact drug efficacy. Thus, understanding ivermectin metabolism and assessing this impact on Plasmodium liver stage development is critical. Using primary human hepatocytes (PHHs), we characterized ivermectin metabolism and evaluated the efficacy of ivermectin and its primary metabolites M1 (3″-O-demethyl ivermectin) and M3 (4-hydroxymethyl ivermectin) against Plasmodium falciparum liver stages. Two different modes of ivermectin exposure were evaluated: prophylactic mode (days 0-3 post-infection) and curative mode (days 3-5 post-infection). We used two different PHH donors and modes to determine the inhibitory concentration (IC50) of ivermectin, M1, M3, and the known anti-malarial drug pyrimethamine, with IC50 values ranging from 1.391 to 14.44, 9.95-23.71, 4.767-8.384, and 0.9073-5.416 µM, respectively. In our PHH model, ivermectin and metabolites M1 and M3 demonstrated inhibitory activity against P. falciparum liver stages in curative treatment mode (days 3-5) and marginal activity in prophylactic treatment mode (days 0-3). Ivermectin had improved efficacy when co-administered with ketoconazole, a specific inhibitor of cytochrome P450 3A4 enzyme. Further studies should be performed to examine ivermectin liver stage efficacy when co-administered with CYP3A4 inhibitors and anti-malarial drugs to understand the pharmacokinetic and pharmacodynamic drug-drug interactions that enhance efficacy against human malaria parasites in vitro.

6.
J Neurosci Res ; 102(1): e25254, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37814994

RESUMO

Ivermectin (IVM), a semi-synthetic macrolide parasiticide, has demonstrated considerable effectiveness in combating internal and external parasites, particularly nematodes and arthropods. Its remarkable ability to control parasites has earned it significant recognition, culminating in Satoshi Omura and William C. Campbell's receipt of the 2015 Nobel Prize in Physiology or Medicine for their contributions to the development of IVM. In recent years, investigations have revealed that IVM possesses antitumor properties. It can suppress the growth of various cancer cells, including glioma, through a multitude of mechanisms such as selective targeting of tumor-specific proteins, inducing programmed cell death, and modulation of tumor-related signaling pathways. Hence, IVM holds tremendous potential as a novel anticancer drug. This review seeks to provide an overview of the underlying mechanisms that enable IVM's capacity to suppress glioma. Furthermore, it aims to elucidate the challenges and prospects associated with utilizing IVM as a new anticancer agent.


Assuntos
Antineoplásicos , Glioma , Humanos , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Ivermectina/história , Glioma/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Prêmio Nobel , Apoptose
7.
J Med Virol ; 96(3): e29552, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511598

RESUMO

Ivermectin has broad-spectrum antiviral activities. Despite the failure in clinical application of COVID-19, it can serve as a lead compound for the development of more effective broad-spectrum antivirals, for which a better understanding of its antiviral mechanisms is essential. We thus searched for potential novel targets of ivermectin in host cells by label-free thermal proteomic profiling using Huh-7 cells. Inositol monophosphatase (IMPase) was found among the proteins with shifted thermal stability by ivermectin. Ivermectin could inhibit IMPase activity and reduce cellular myo-inositol and phosphatidylinositol-4-phosphate levels. On the other hand, inositol could impair the antiviral activity of ivermectin and lithium, an IMPase inhibitor with known antiviral activity. As phosphatidylinositol phosphate is crucial for the replication of many RNA viruses, inhibition of cellular myo-inositol biosynthesis may be an important antiviral mechanism of ivermectin. Hence, inhibition of IMPase could serve as a potential target for broad-spectrum antiviral development.


Assuntos
5'-Nucleotidase , Ivermectina , Monoéster Fosfórico Hidrolases , Humanos , Ivermectina/farmacologia , Proteômica , Inositol/farmacologia , Antivirais/farmacologia
8.
Cytokine ; 173: 156433, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972479

RESUMO

Severe COVID-19 pneumonia is a principal cause of death due to cascade of hyper inflammatory condition that leading to lung damage. Therefore, an effective therapy to countercurrent the surge of uncontrolled inflammation is mandatory to propose. Anti-interlukin-6 receptor antagonist monoclonal therapy, tocilizumab (TCZ) showed potential results in COVID-19 patients. This study aimed to emphasize the factors associated with mortality in COVID-19 patients that treated with tocilizumab and may influence the level of serum IL-6. A retrospective cohort study included all patients with clinical parameters that pointed to presence of cytokines storm and treated with one or more doses of TCZ beside the regular protocol of COVID-19 pneumonia. The factors that influence the mortality in addition to the level of serum IL-6 were analyzed. A total of 377 patients were included, 69.5 % of them received only one dose of TCZ which started mainly at the third day of admission. The mortality rate was 29.44 %. Regardless the time of starting TCZ, just one dose was fair enough to prevent bad consequence; OR = 0.04, P = 0.001.However, in spite of protective action of TCZ, older age and female sex were significant risk factors for mortality, P = 0.001 and 0.01 respectively, as well heart disease. Moreover, increasing the level of neutrophil, AST and IL-6 were associated with bad prognosis. In the same line, treatment with ivermectin, chloroquine and remdesivir inversely affect the level of IL-6. Early treatments of COVID-19 pneumonia with at least one dose of tocilizumab minimized the fatality rate.


Assuntos
COVID-19 , Humanos , Feminino , SARS-CoV-2 , Citocinas , Estudos Retrospectivos , Interleucina-6 , Tratamento Farmacológico da COVID-19 , Prognóstico
9.
Arch Microbiol ; 206(2): 78, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277061

RESUMO

Varicellovirus bovinealpha 1 (formerly bovine alphaherpesvirus type 1, BoAHV-1) is associated with several syndromes in cattle, including respiratory disease and is one of the main agents involved in the bovine respiratory disease complex (BRDC). Its infectious cycle is characterized by latent infections with sporadic virus reactivation and transmission. Although the acute disease can be prevented by the use of vaccines, specific therapeutic measures are not available. Ivermectin (IVM) is a semi-synthetic avermectin with a broad-spectrum antiparasitic activity, which has previously shown to have potential as an antiviral drug. In this study, IVM antiviral activity against BoAHV-1 was characterized in two cell lines (MDBK [Madin Darby bovine kidney] and BT [bovine turbinate]), including the measurement of intracellular drug accumulation within virus-infected cells. IVM antiviral activity was assessed at three different drug concentrations (1.25, 2.5 and 5 µM) after incubation for 24, 48 and 72 h. Slight cytotoxicity was only observed with 5 µM IVM. Even the lowest IVM dose was able to induce a significant reduction in virus titers in both cell lines. These findings indicate that the antiviral effects of IVM were evident in our experimental model within the range of concentrations achievable through therapeutic in vivo administration. Consequently, additional in vivo trials are necessary to validate the potential utility of these results in effectively managing BoAHV-1 in infected cattle.


Assuntos
Ivermectina , Varicellovirus , Animais , Bovinos , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Antivirais/farmacologia
10.
Eur Biophys J ; 53(1-2): 15-25, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233601

RESUMO

The α7 nicotinic acetylcholine receptor is a member of the nicotinic acetylcholine receptor family and is composed of five α7 subunits arranged symmetrically around a central pore. It is localized in the central nervous system and immune cells and could be a target for treating Alzheimer's disease and schizophrenia. Acetylcholine is a ligand that opens the channel, although prolonged application rapidly decreases the response. Ivermectin was reported as one of the positive allosteric modulators, since the binding of Ivermectin to the channel enhances acetylcholine-evoked α7 currents. One research has suggested that tilting motions of the nicotinic acetylcholine receptor are responsible for channel opening and activation. To verify this hypothesis applies to α7 nicotinic acetylcholine receptor, we utilized a diffracted X-ray tracking method to monitor the stable twisting and tilting motion of nAChR α7 without a ligand, with acetylcholine, with Ivermectin, and with both of them. The results show that the α7 nicotinic acetylcholine receptor twists counterclockwise with the channel transiently opening, transitioning to a desensitized state in the presence of acetylcholine and clockwise without the channel opening in the presence of Ivermectin. We propose that the conformational transition of ACh-bound nAChR α7 may be due to the collective twisting of the five α7 subunits, resulting in the compression and movement, either downward or upward, of one or more subunits, thus manifesting tilting motions. These tilting motions possibly represent the transition from the resting state to channel opening and potentially to the desensitized state.


Assuntos
Receptores Nicotínicos , Receptor Nicotínico de Acetilcolina alfa7 , Receptor Nicotínico de Acetilcolina alfa7/química , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Acetilcolina/química , Acetilcolina/metabolismo , Ligantes , Ivermectina/farmacologia , Receptores Nicotínicos/química , Receptores Nicotínicos/metabolismo , Regulação Alostérica
11.
Malar J ; 23(1): 54, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383367

RESUMO

BACKGROUND: Mass Drug Administration (MDA) has become a mainstay for the control of several diseases over the last two decades. Successful implementation of MDA programmes requires community participation and can be threatened by systematic non-participation. Such concerns are particularly pertinent for MDA programmes against malaria, as they require multi-day treatment over several consecutive months. Factors associated with non-participation to the MDA campaign with ivermectin (IVM) and dihydroartemisinin-piperaquine (DHP) implemented within the MASSIV cluster randomized trial were determined. METHODS: Coverage data was extracted from the MASSIV trial study database, with every datapoint being a directly observed therapy (DOT). A complete month of MDA was classified as receiving all three daily doses of treatment. For both ivermectin and DHP, ordinal logistic regression was used to identify individual and household level variables associated with non-participation. RESULTS: For ivermectin, 51.5% of eligible participants received all 3 months of treatment while 30.7% received either one or two complete months. For DHP, 56.7% of eligible participants received all 3 months of treatment and 30.5% received either one or two complete months. Children aged 5-15 years and adults aged more than 50 years were more likely to receive at least one complete month of MDA than working age adults, both for ivermectin (aOR 4.3, 95% CI 3.51-5.28 and aOR of 2.26, 95% CI 1.75-2.95) and DHP (aOR 2.47, 95%CI 2.02-3.02 and aOR 1.33, 95%CI 1.01-1.35), respectively. Members of households where the head received a complete month of MDA were more likely to themselves have received a complete month of MDA, both for ivermectin (aOR 1.71, 95%CI 1.35-2.14) and for DHP (aOR 1.64, 95%CI 1.33-2.04). CONCLUSION: Personal and household-level variables were associated with participation in the MDA programme for malaria control. Specific strategies to (increase participation amongst some groups may be important to ensure maximum impact of MDA strategies in achieving malaria elimination. TRIAL REGISTRATION: The MASSIV trial is registered under NCT03576313.


Assuntos
Antimaláricos , Artemisininas , Malária , Piperazinas , Quinolinas , Adulto , Criança , Humanos , Ivermectina/uso terapêutico , Malária/prevenção & controle , Malária/tratamento farmacológico , Administração Massiva de Medicamentos , Quinolinas/uso terapêutico , Fatores de Risco , Pré-Escolar , Adolescente , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Graefes Arch Clin Exp Ophthalmol ; 262(4): 1281-1288, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37910180

RESUMO

BACKGROUND: To evaluate the efficacy of topical ivermectin 1% ointment, for the treatment of Demodex blepharitis. METHODS: A retrospective study was designed to review electronic medical records of patients seen between January 2017 and December 2022, who had a diagnosis of Demodex blepharitis, treated with topical ivermectin 1% with at least 6 months of follow-up (Centro de Ojos Quilmes, Buenos Aires, Argentina). The presence of collarettes was graded from 0 to 4. An imaging system (Keratograph) was used, to evaluate tear meniscus height (TMH), non-invasive tear break-up time (NIKBUT), and degree of conjunctival redness. In addition, the ocular surface disease index (OSDI) test was performed. Results were compared before and after ivermectin treatment, which was performed once a day for 2 months. RESULTS: A total of 2157 patients (4314 eyes) were included. The mean age was 50.43 ± 15.3 years, and the follow-up time was 26.1 ± 8.5 months. No one discontinued treatment due to intolerance, although 14 cases (0.6 %) reported occasional discomfort. The grade of collarettes decreased with statistical significance, from 3.37 ± 0.7 to 0.1 ± 0.3 (p < 0.01), as well as conjunctival redness from 1.32 ± 0.3 to 0.94 ± 0.4 (p < 0.01) and OSDI score from 58.74 ± 17.9 to 17.1 ± 10.5 (p = 0.02). TMH and NIKBUT improved without statistical difference. CONCLUSION: Treatment with ivermectin 1% topical ointment, once daily for 2 months, was effective in reducing the presence of collarettes and in improving symptoms in patients with Demodex blepharitis.


Assuntos
Blefarite , Infestações por Ácaros , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Ivermectina , Estudos Retrospectivos , Blefarite/diagnóstico , Blefarite/tratamento farmacológico , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/tratamento farmacológico , Pomadas
13.
J Infect Chemother ; 30(6): 536-543, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38154616

RESUMO

BACKGROUND: Ivermectin is an antiparasitic drug administered to hundreds of millions of people worldwide. Fundamental research suggests that ivermectin is effective against coronavirus disease 2019 (COVID-19); therefore, we investigated the efficacy and safety of ivermectin as a COVID-19 treatment option. METHODS: This multi-regional (Japan and Thailand), multicenter, placebo-controlled, randomized, double-blind, parallel-group, Phase III study evaluated the efficacy and safety of ivermectin in patients with mild COVID-19 (IVERMILCO Study). The participants took a specified number of the investigational product (ivermectin or placebo) tablets of, adjusted to a dose of 0.3-0.4 mg/kg, orally on an empty stomach once daily for three days. The primary efficacy endpoint was the time at which clinical symptoms first showed an improving trend by 168 h after investigational product administration. RESULTS: A total of 1030 eligible participants were assigned to receive the investigational product; 502 participants received ivermectin and 527 participants received a placebo. The primary efficacy endpoint was approximately 96 h (approximately four days) for both ivermectin and placebo groups, which did not show statistically significant difference (stratified log-rank test, p = 0.61). The incidence of adverse events and adverse drug reactions did not show statistically significant differences between the ivermectin and placebo groups (chi-square test, p = 0.97, p = 0.59). CONCLUSIONS: The results show that ivermectin (0.3-0.4 mg/kg), as a treatment for patients with mild COVID-19, is ineffective; however, its safety has been confirmed for participants, including minor participants of 12 years or older (IVERMILCO Study ClinicalTrials.gov number, NCT05056883.).


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Ivermectina/efeitos adversos , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Japão/epidemiologia , Tailândia/epidemiologia , Método Duplo-Cego , Resultado do Tratamento
14.
Exp Parasitol ; 261: 108751, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604302

RESUMO

Anisakiasis is a parasitic disease transmitted through the consumption of raw or undercooked fish and cephalopods that are infected with larvae of Anisakis simplex (sensu stricto) or Anisakis pegreffii. The purpose of this study was to investigate how A. simplex (s. s.) responds to the influence of anthelmintics such as ivermectin (IVM) and pyrantel (PYR). In vitro experiments were conducted using larvae at two developmental stages of A. simplex (s. s.) (L3 and L4) obtained from Baltic herring (Clupea harengus membras). Larvae were cultured with different concentrations of IVM or PYR (1.56, 3.125, and 6.25 µg/mL) for various durations (3, 6, 9, and 12 h) under anaerobic conditions (37 °C, 5% CO2). The gene expression of actin, ABC transporter, antioxidant enzymes, γ-aminobutyric acid receptors, and nicotinic acetylcholine receptors, as well as the oxidative status were analyzed. The results showed that A. simplex (s. s.) L3 stage had lower mobility when cultured with PYR compared to IVM. The analysis of relative gene expression revealed significant differences in the mRNA level of ABC transporters after treatment with IVM and PYR, compared to the control group. Similar patterns were observed in the gene expression of antioxidant enzymes in response to both drugs. Furthermore, the total antioxidant capacity (TAC) and glutathione S-transferase (GST) activity were higher in the treatment groups than in the control group. These findings suggest a relationship between the expression of the studied genes, including those related to oxidative metabolism, and the effectiveness of the tested drugs.


Assuntos
Anisakis , Anti-Helmínticos , Ivermectina , Larva , Pirantel , Animais , Anisakis/efeitos dos fármacos , Anisakis/genética , Anisakis/crescimento & desenvolvimento , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Larva/genética , Anti-Helmínticos/farmacologia , Pirantel/farmacologia , Actinas/metabolismo , Actinas/genética , Actinas/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/genética , Receptores Nicotínicos/efeitos dos fármacos , Xenobióticos/farmacologia , Xenobióticos/metabolismo , Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Anisaquíase/parasitologia , Anisaquíase/veterinária , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/efeitos dos fármacos , Catalase/genética , Catalase/metabolismo , Catalase/efeitos dos fármacos , Peixes/parasitologia , Doenças dos Peixes/parasitologia
15.
Pharmacology ; 109(1): 1-9, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37879298

RESUMO

INTRODUCTION: Ivermectin (IVM) is a broad-spectrum anti-parasitic agent with potential antibacterial, antiviral, and anti-cancer effects. There are limited studies on the effects of IVM on cardiovascular diseases, so the present study sought to determine the effects of pre-treatment with IVM on myocardial ischemia in both ex vivo and in vivo. METHODS: In the ex vivo part, two groups of control and treated rats with IVM (0.2 mg/kg) were examined for cardiac function and arrhythmias by isolated heart perfusion. In the in vivo part, four groups, namely, control, IVM, Iso (MI), and Iso + IVM 0.2 mg/kg were used. Subcutaneous injection of isoproterenol (100 mg/kg/day) for 2 consecutive days was used for the induction of myocardial infarction (MI) in male Wistar rats. Then electrocardiogram, hemodynamic factors, cardiac hypertrophy, and malondialdehyde (MDA) levels were investigated. RESULTS: The ex vivo results showed that administration of IVM induces cardiac arrhythmia and decreases the left ventricular maximal rate of pressure increase (contractility) and maximal rate of pressure decline (relaxation). The isoproterenol-induced MI model used as an in vivo model showed that cardiac hypertrophy were increased with no improvement in the hemodynamic and electrocardiogram pattern in the IVM-treated group in comparison to MI (Iso) group. However, the MDA level was lower in the IVM-treated group. CONCLUSION: IVM pre-treatment demonstrates detrimental effects in cardiac ischemia through exacerbation of cardiac arrhythmia, myocardial dysfunction, and increased cardiac hypertrophy. Therefore, the use of IVM in ischemic heart patients should be done with great caution.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Humanos , Ratos , Masculino , Animais , Isoproterenol/toxicidade , Ivermectina/efeitos adversos , Ratos Wistar , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Cardiomegalia , Miocárdio
16.
Parasitol Res ; 123(5): 221, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787430

RESUMO

Ivermectin mass drug administration has been used for decades to target human and veterinary ectoparasites, and is currently being considered for use against malaria vectors. Although there have been few reports of resistance to date in human ectoparasites, we must anticipate the development of resistance in mosquitoes in the future. Hence, through this review, we mapped the existing evidence on ivermectin resistance mechanisms in human ectoparasites. A search was conducted on the 8th November 2023 through databases, PubMed, Web of Science, and Google Scholar, using terms related to ivermectin, human and veterinary ectoparasites, and resistance. Abstracts (5893) were screened by JFA and CK. Data on the study organism, the type of resistance, the analysis methods, and, where applicable, the gene loci of interest were extracted from the studies. Details of the methodology and results of each study were summarised narratively and in a table. Eighteen studies were identified describing ivermectin resistance in ectoparasites. Two studies described target site resistance; and 16 studies reported metabolic resistance and/or changes in efflux pump expression. The studies investigated genetic mutations in resistant organisms, detoxification, and efflux pump expression in resistant versus susceptible organisms, and the effect of synergists on mortality or detoxification enzyme/efflux pump transcription. To date, very few studies have been conducted examining the mechanisms of ivermectin resistance in ectoparasites, with only two on Anopheles spp. Of the existing studies, most examined detoxification and efflux pump gene expression, and only two studies in lice investigated target-site resistance. Further research in this field should be encouraged, to allow for close monitoring in ivermectin MDA programmes, and the development of resistance mitigation strategies.


Assuntos
Ivermectina , Ivermectina/farmacologia , Animais , Humanos , Resistência a Medicamentos/genética , Inseticidas/farmacologia , Ectoparasitoses/parasitologia , Ectoparasitoses/veterinária , Ectoparasitoses/tratamento farmacológico , Resistência a Inseticidas/genética
17.
Parasitol Res ; 123(4): 180, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592544

RESUMO

Because of recent reports of praziquantel resistance in schistosome infections, there have been suggestions to employ ivermectin as a possible alternative, especially as its chemical composition is different from that of praziquantel, so cross-resistance is not expected. In order to ascertain possible damage and elimination of worms, we used ivermectin by oral gavage in infected mice, at a high dose (30.1 mg/kg, bordering toxicity). We also tested the efficacy of the drug at various times postinfection (PI), to check on possible effect on young and mature stages of the parasites. Thus, we treated mice on days 21 and 22 or on days 41 and 42 and even on days 21, 22, 41, and 42 PI. None of the treatment regimens resulted in cure rates or signs of lessened pathology in the mice. We also compared the effect of ivermectin to that of artemisone, an artemisinin derivative which had served us in the past as an effective anti-schistosome drug, and there was a stark difference in the artemisone's efficacy compared to that of ivermectin; while ivermectin was not effective, artemisone eliminated most of the worms, prevented egg production and granulomatous inflammatory response. We assume that the reported lack of activity of ivermectin, in comparison with praziquantel and artemisinins, originates from the difference in their mode of action. In wake of our results, we suggest that ivermectin is not a suitable drug for treatment of schistosomiasis.


Assuntos
Artemisininas , Schistosomatidae , Esquistossomose , Animais , Camundongos , Praziquantel/uso terapêutico , Ivermectina/uso terapêutico , Esquistossomose/tratamento farmacológico
18.
Parasitol Res ; 123(5): 226, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814484

RESUMO

In this study, 858 novel long non-coding RNAs (lncRNAs) were predicted as sensitive and resistant strains of Haemonchus contortus to ivermectin. These lncRNAs underwent bioinformatic analysis. In total, 205 lncRNAs significantly differed using log2 (difference multiplicity) > 1 or log2 (difference multiplicity) < - 1 and FDR < 0.05 as the threshold for significant difference analysis. We selected five lncRNAs based on significant differences in expression, cis-regulation, and their association with the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways. These expressions of lncRNAs, namely MSTRG.12610.1, MSTRG.8169.1, MSTRG.6355.1, MSTRG.980.1, and MSTRG.9045.1, were significantly downregulated. These findings were consistent with the results of transcriptomic sequencing. We further investigated the relative expression of target gene mRNAs and the regulation of mRNA and miRNA, starting with lncRNA cis-regulation of mRNA, and constructed a lncRNA-mRNA-miRNA network regulation. After a series of statistical analyses, we finally screened out UGT8, Unc-116, Fer-related kinase-1, GGPP synthase 1, and sart3, which may be involved in developing drug resistance under the regulation of their corresponding lncRNAs. The findings of this study provide a novel direction for future studies on drug resistance targets.


Assuntos
Resistência a Medicamentos , Haemonchus , Ivermectina , RNA Longo não Codificante , Animais , Haemonchus/genética , Haemonchus/efeitos dos fármacos , RNA Longo não Codificante/genética , Ivermectina/farmacologia , Resistência a Medicamentos/genética , Hemoncose/parasitologia , Hemoncose/veterinária , Anti-Helmínticos/farmacologia , MicroRNAs/genética , Biologia Computacional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos
19.
Pestic Biochem Physiol ; 201: 105899, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685208

RESUMO

This study investigated the function of the MDR49 gene in Aedes aegypti. MDR49 mutants were constructed using CRISPR/Cas9 technology; the mutation led to increased sensitivity to ivermectin (LC50: from 1.3090 mg L-1 to 0.5904 mg L-1), and a reduction in midgut trypsin activity. These findings suggest that the P-gp encoded by MDR49 confers resistance to ivermectin and impacts the reproductive function in Ae. aegypti. RNA interference technology showed that knockdown of MDR49 gene resulted in a significant decrease in the expression of VGA1 after a blood meal, as well as a decrease in the number of eggs laid and their hatching rate. LC-MS revealed that following ivermectin treatment, the MDR493d+2s/3d+2s strain larvae exhibited significantly higher drug concentrations in the head and fat body compared to the wild type. Modeling of inward-facing P-gp and molecular docking found almost no difference in the affinity of P-gp for ivermectin before and after the mutation. However, modeling of the outward-facing conformation demonstrated that the flexible linker loop between TM5 and TM6 of P-gp undergoes changes after the mutation, resulting in a decrease in trypsin activity and an increase in sensitivity to ivermectin. These results provide useful insights into ivermectin resistance and the other roles played by the MDR49 gene.


Assuntos
Aedes , Proteínas de Insetos , Ivermectina , Animais , Aedes/efeitos dos fármacos , Aedes/genética , Aedes/metabolismo , Ivermectina/farmacologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Tripsina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Fertilidade/efeitos dos fármacos , Resistência a Inseticidas/genética , Inibidores da Tripsina/metabolismo , Inibidores da Tripsina/farmacologia , Simulação de Acoplamento Molecular , Inseticidas/farmacologia
20.
Immunopharmacol Immunotoxicol ; 46(2): 183-191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38224264

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a pulmonary fibrotic disease characterized by a poor prognosis, which its pathogenesis involves the accumulation of abnormal fibrous tissue, inflammation, and oxidative stress. Ivermectin, a positive allosteric modulator of GABAA receptor, exerts anti-inflammatory and antioxidant properties in preclinical studies. The present study investigates the potential protective effects of ivermectin treatment in rats against bleomycin-induced IPF. MATERIALS AND METHODS: The present study involved 42 male Wistar rats, which were divided into five groups: control (without induction of IPF), bleomycin (IPF-induced by bleomycin 2.5 mg/kg, by intratracheal administration), and three fibrosis groups receiving ivermectin (0.5, 1, and 3 mg/kg). lung tissues were harvested for measurement of oxidative stress [via myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione (GSH)] and inflammatory markers (tumor necrosis factor-α [TNF-α], interleukin-1ß [IL-1ß], and transforming growth factor-ß [TGF-ß]). Histological assessments of tissue damage were performed using hematoxylin-eosin (H&E) and Masson's trichrome staining methods. RESULTS: The induction of fibrosis via bleomycin was found to increase levels of MPO as well as TNF-α, IL-1ß, and TGF-ß while decrease SOD activity and GSH level. Treatment with ivermectin at a dosage of 3 mg/kg was able to reverse the effects of bleomycin-induced fibrosis on these markers. In addition, results from H&E and Masson's trichrome staining showed that ivermectin treatment at this same dose reduced tissue damage and pulmonary fibrosis. CONCLUSION: The data obtained from this study indicate that ivermectin may have therapeutic benefits for IPF, likely due to its ability to reduce inflammation and mitigate oxidative stress-induced toxicity.


Assuntos
Fibrose Pulmonar , Ratos , Masculino , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/prevenção & controle , Bleomicina/efeitos adversos , Ivermectina/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Ratos Wistar , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/patologia , Pulmão/metabolismo , Estresse Oxidativo , Fator de Crescimento Transformador beta , Glutationa/metabolismo , Superóxido Dismutase/metabolismo
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