In vitro efficacy of latex and purified papain from Carica papaya against Strongyloides venezuelensis eggs and larvae

ABSTRACT Latex from Carica papaya is rich in bioactive compounds, especially papain, which may help to control parasitic diseases. This study evaluated the efficacy of latex from C. papaya and purified papain against Strongyloides venezuelensis. The Egg Hatching Test (EHT) and the Larval Motility Test (LMT) using fresh and frozen latex (250mg/mL), lyophilized latex (34mg/mL), and purified papain (2.8 mg/mL) were performed. Albendazole (0.025 mg/mL) and ivermectin (316 ppm) were used as positive controls. EHT and LMT were carried out through the incubation of each solution with S. venezuelensis eggs or larvae (± 100 specimens), and results were analyzed after 48h (EHT) or 24, 48, and 72h (LMT). EHT showed that latex preparations at higher concentrations (1:10 to 1:100) resulted in partial or complete destruction of eggs and larvae inside the eggs. The result from the 1:1,000 dilution was similar to the positive control. LMT showed effectiveness in all the tested dilutions compared to negative controls. Purified papain showed a dose-dependent response in the EHT. Purified papain (2.8 mg/ mL) showed similar results to lyophilized latex at 1:1,000 in the EHT. Latex and purified papain from C. papaya were effective against S. venezuelensis eggs and larvae in vitro, suggesting their potential use as an alternative treatment for strongyloidiasis.

Prevalence of strongyloides in Northern Thailand and treatment with ivermectin vs albendazole.

The stools of 697 cases were examined by agar plate technique at Tambon Makam Luang, Sun Pa Tong district, Chiang Mai; there were Strongyloides stercoralis 15.9%,Opisthorchis viverrini 5.1%, intestinal fluke 0.1%. Treatment with ivermectin 78 cases and albendazole 33 cases of strongyloidiasis gave cure rates at 98.7% and 78.7%, respectively. Alkaline phosphatase in some patients were increased at mild level after treatment. Side effects in ivermectin group were anorexia, nausia, diarrhea, diffuse itching and drowsiness; and in albendazole group were nausia and diarrhea. The efficacy of single dose and mild side effects suggest ivermectin as drug of choice for strongyloidiasis treatment.

Tratamento de ratos, experimentalmente infectados pelo Strongyloides venezuelensis, através da ivermectina administrada por via oral / The treatment of rats experimentally infected with Strongyloides venezuelensis by orally administered ivermectin

Em modelo experimental, baseado na infecção de ratos pelo Strongyloides venezuelensis, foi avaliada a atividade terapêutica de duas preparações de ivermectina, para usos veterinário e humano. Houve interesse em verificar a efetividade em relação a vermes adultos e formas larvárias. A administração dos fármacos ocorreu sempre por via oral e a posologia correspondeu à dose única de 0,2mg/kg. Considerados os vermes adultos e as formas larvárias, o produto para emprego veterinário propiciou eliminações expressas pelas porcentagens de 98,0% e 84,2%; quanto à outra preparação, as taxas situaram-se em 59,3% e 73,0%, respectivamente. O estudo revelou, então, utilidade do anti-helmíntico quando usada a via oral e, também, mostrou significativa ação sobre as formas larvárias, certamente valiosa quando vigente a modalidade disseminada da estrongiloidíase.

Strongyloides venezuelensis experimental infection in rats was treated by two different oral preparations of ivermectin, 0.2 mg/kg. One was a human formula used by WHO in the treatment of onchocerciasis; the other was a veterinary preparation. Adult worms and larvae were evaluated. The human formulation cleared both forms in 59.3% (adult worms) and 73.0% (larvae), whereas the veterinary one cleared 98.0% and 84.2%, respectively. The antilarval action is very useful when treating systemic strongyloidiasis.

Inactivation of strongyloides stercoralis filariform larvae in vitro by six Jamaican plant extracts and three commercial antihelmintics

In vitro bioassay of (a) aqueous methanol extracts (AME) of the green leaves of mimosa (Mimosa pudica), love weed (Cuscuta americana), vervine (Stachytarpheta jamaicensis), chicken weed (Salvia serotina) and breadfruit (Artocarpus altilis); (b) methanol-water fraction (MWF) of breadfruit leaves, and (c) commercially available drugs albendazole, thiabendazole and levamisole were assayed for nematode inactivating potential, using filariform larvae of Strongyloides stercoralis. Test larvae were obtained from a 10-day-old charcoal coproculture. Bioassays were conducted in Locke's solution, using 100 larvae in each of three replicates. Inactivation was recorded microscopically at 1, 2, 6 and 12 hours, then every 24 hours up to 5 days' incubation. It(50) (time for inactivation of 50%of larvae) values read: levamisole and mimosa extract < 1 hour; love weed extract, approximately 2 hours; breadfruit (MWF), 9.5 hours; chicken weed, 20 hours; albendazole, 35 hours; breadfruit (AME), 49 hours; thiabendazole, 74 hours and vervine extract, 81.5 hours. It(95) values followed a similar trend, and were approximately double the It(50) measures. A potential role for locally available natural products in the treatment of strongyloidiasis is highlighted

Avaliaçäo da atividade terapêutica do Albendazol em ratos experimentalmente infectados com Strongyloides venezuelensis / Evaluation of the therapeutic activity in rats experimentally infected with Strongyloides venezuelensis

Com a finalidade de demarcar mais precisamente o espectro de açäo do albendazol, foi estudada a atividade terapêutica desse anti-helmíntico em ratos experimentalmente infectados com Strongyloides venezuelensis, tendo sido usada, como termo de comparaçäo, a açäo do cambendazol e do mebendazol, dois outros benzimidazólicos. Os três compostos mostraram-se eficientes quando utilizadas doses únicas de 6,75 12,5, 25 e 50 mg/kg, pois motivaram desaparecimento total das formas adultas no intestino. Com a posologia de 5 mg/kg sucederam porcentagens médias de reduçöes dos números de vermes de 87%, 98% e 80%, respectivamente, como decorrência do emprego do albendazol, do cambendazol e do mebendazol, traduzindo superioridade da segunda droga citada

Strongyloides ratti and S. stercoralis: effects of Cambendazole, Thiabendazole and Mebendazole in vitro

Os efeitos da incubaçäo de três antihelmínticos, tiabendazol, mebendazol e cambendazol sobre Strongyloides foram comparados. Nenhuma droga afetou a eclosäo dos ovos de S. ratti ou a viabilidade de larvas infectantes ou vermes adultos parasitários, mas todas as três inibiram a formaçäo de larvas de S. ratti. Além disso, cambendazol, mas näo tiabendazol ou mebendazol, diminuiu a viabilidade de larvas de primeiro e segundo estágio de S. ratti. As três drogas näo tiveram efeito sobre vermes adultos de vida livre isolados, de S. stercoralis, mas todas evitaram o desenvolvimento de larvas rabditiformes de S. stercoralis. Tianbendazol e mebendazol näo tiveram efeito sobre a infectividade de larvas infectantes de S. ratti ou de S. stercoralis, mas a infecçäo com esses vermes foi anulada por incubaçäo prévia com cambendazol. Esses resultados indicam que cambendazol age de modo diferente das outras duas drogas. Uma vez que ele é ativo contra larvas migrando através dos tecidos, é potencialmente de muito maior valor que a tiabendazol ou mebendazol na terapêutica da estrongilodíase

Dermarcaçäo da atividade anti-helmíntica do albendazol. Estudo referente à estrongiloidíase humana / Delimitation of the anthelmintic activity of albendazole. Study concerning human strongyloidiasis

Os Autores utilizaram novo anti-helmíntico, o albendazol, no tratamento de 32 pessoas com estrongiloidíase. A casuística foi composta por adultos, de ambos os sexos, que receberam, pela via oral, dose cotidiana única de 400 mg, repetida em três oportunidades intervaladas por períodos de 24 horas. O controle da terapêutica sucedeu através de exames das fezes realizados sete, 14 e 21 dias após o término da administraçäo, tendo sido empregado o método de Rugai, Mattos e Brisola. A porcentagem de curas verificada correspondeu a 28,1% e, ao lado da boa tolerância observada, essa constataçäo demonstrou baixa eficácia do medicamento em apreço no combate à infecçäo causada pelo Strongyloides stercoralis, a despeito de méritos comprovados em investigaçöes anteriores e concernentes a outras parasitoses intestinais