scholarly journals In vitro effects of artesunate on the survival of worm pairs and egg production of Schistosoma mansoni

2009 ◽  
Vol 83 (1) ◽  
pp. 7-11 ◽  
Author(s):  
Y. Mitsui ◽  
M. Miura ◽  
Y. Aoki

AbstractThe effect of artesunate (ART) on the survival time of adult worm pairs of Schistosoma mansoni and on their egg output during in vitro culture was assessed. ART significantly decreased the survival time of both paired male and female worms at concentrations of 5, 10, 20 and 40 mg l− 1 during in vitro cultivation. An inhibitory effect of ART on the daily egg output of paired female worms during in vitro cultivation was also observed.

2009 ◽  
Vol 64 (11-12) ◽  
pp. 793-797 ◽  
Author(s):  
Caio G. Braguine ◽  
Eveline S. Costa ◽  
Lizandra G. Magalhães ◽  
Vanderlei Rodrigues ◽  
Ademar A. da Silva Filho ◽  
...  

Chemical investigation of the EtOAc fraction (EF) obtained from the ethanolic extract of Zanthoxylum naranjillo (Rutaceae) leaves (EE) by preparative HPLC resulted in the isolation of protocatechuic acid (1), gallic acid (2), p-hydroxybenzoic acid (3), and 5-Ocaffeoylshikimic acid (4). This is the fi rst time that the presence of compounds 1 - 4 in Z. naranjillo has been reported. Compounds 1 - 4, the EE, and EF were tested in vitro against Schistosoma mansoni adult worms. The results showed that the S. mansoni daily egg production decreased by 29.8%, 13.5%, 28.4%, 17.7%, 16.3%, and 6.4%, respectively. Compounds 1 and 3 were also able to separate adult worm pairs into male and female. This activity may be correlated with the reduction in egg production, since 1 and 3 showed better inhibitory properties compared with 2 and 4.


Author(s):  
Annika S. Mokosch ◽  
Stefanie Gerbig ◽  
Christoph G. Grevelding ◽  
Simone Haeberlein ◽  
Bernhard Spengler

AbstractSchistosoma mansoni is a parasitic flatworm causing schistosomiasis, an infectious disease affecting several hundred million people worldwide. Schistosomes live dioeciously, and upon pairing with the male, the female starts massive egg production, which causes pathology. Praziquantel (PZQ) is the only drug used, but it has an inherent risk of resistance development. Therefore, alternatives are needed. In the context of drug repurposing, the cancer drug imatinib was tested, showing high efficacy against S. mansoni in vitro. Besides the gonads, imatinib mainly affected the integrity of the intestine in males and females. In this study, we investigated the potential uptake and distribution of imatinib in adult schistosomes including its distribution kinetics. To this end, we applied for the first time atmospheric-pressure scanning microprobe matrix-assisted laser desorption/ionization mass spectrometry imaging (AP-SMALDI MSI) for drug imaging in paired S. mansoni. Our results indicate that imatinib was present in the esophagus and intestine of the male as early as 20 min after in vitro exposure, suggesting an oral uptake route. After one hour, the drug was also found inside the paired female. The detection of the main metabolite, N-desmethyl imatinib, indicated metabolization of the drug. Additionally, a marker signal for the female ovary was successfully applied to facilitate further conclusions regarding organ tropism of imatinib. Our results demonstrate that AP-SMALDI MSI is a useful method to study the uptake, tissue distribution, and metabolization of imatinib in S. mansoni. The results suggest using AP-SMALDI MSI also for investigating other antiparasitic compounds and their metabolites in schistosomes and other parasites. Graphical abstract


1989 ◽  
Vol 61 (02) ◽  
pp. 254-258 ◽  
Author(s):  
Margaret L Rand ◽  
Peter L Gross ◽  
Donna M Jakowec ◽  
Marian A Packham ◽  
J Fraser Mustard

SummaryEthanol, at physiologically tolerable concentrations, inhibits platelet responses to low concentrations of collagen or thrombin, but does not inhibit responses of washed rabbit platelets stimulated with high concentrations of ADP, collagen, or thrombin. However, when platelet responses to high concentrations of collagen or thrombin had been partially inhibited by prostacyclin (PGI2), ethanol had additional inhibitory effects on aggregation and secretion. These effects were also observed with aspirin- treated platelets stimulated with thrombin. Ethanol had no further inhibitory effect on aggregation of platelets stimulated with ADP, or the combination of ADP and epinephrine. Thus, the inhibitory effects of ethanol on platelet responses in the presence of PGI2 were very similar to its inhibitory effects in the absence of PGI2, when platelets were stimulated with lower concentrations of collagen or thrombin. Ethanol did not appear to exert its inhibitory effects by increasing cyclic AMP above basal levels and the additional inhibitory effects of ethanol in the presence of PGI2 did not appear to be brought about by further increases in platelet cyclic AMP levels.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 312
Author(s):  
Magdalena Dunowska ◽  
Sayani Ghosh

Feline infectious peritonitis (FIP) is a sporadic fatal disease of cats caused by a virulent variant of feline coronavirus (FCoV), referred to as FIP virus (FIPV). Treatment options are limited, and most of the affected cats die or are euthanized. Anecdotally, doxycycline has been used to treat FIP-affected cats, but there are currently no data to support or discourage such treatment. The aim of this study was to establish whether doxycycline inhibits replication of FIPV in vitro. The virus was cultured in Crandell-Rees feline kidney cells with various concentrations of doxycycline (0 to 50 µg/mL). The level of FIPV in cultures was determined by virus titration and FCoV-specific reverse-transcription quantitative PCR. Cell viability was also monitored. There was no difference in the level of infectious virus or viral RNA between doxycycline-treated and untreated cultures at 3, 12- and 18-hours post-infection. However, at 24 h, the growth of FIPV was inhibited by approximately two logs in cultures with >10 µg/mL doxycycline. This inhibition was dose-dependent, with inhibitory concentration 50% (IC50) 4.1 µg/mL and IC90 5.4 µg/mL. Our data suggest that doxycycline has some inhibitory effect on FIPV replication in vitro, which supports future clinical trials of its use for the treatment of FIP-affected cats.


1996 ◽  
Vol 38 (6) ◽  
pp. 423-426 ◽  
Author(s):  
Leo Roberto Barth ◽  
Ana Paula Morais Fernandes ◽  
Vanderlei Rodrigues

Observation of Schistosoma mansoni oviposition during in vitro culture of adult worms for a maximum period of 10 days showed three well distinct phases in the kinetics of oviposition: an initial phase with low egg production, a period of maximum oviposition and finally a progressive reduction in the number of eggs during the late phases of culture. The kinetics of oviposition and the number of eggs laid by the parasites are influenced by the number of worm pairs per amount of RPMI 1640 medium, time of parasite development in the vertebrate host and type of serum utilized in the culture medium.


Reproduction ◽  
2009 ◽  
Vol 138 (3) ◽  
pp. 471-482 ◽  
Author(s):  
Mirjan Thys ◽  
Hans Nauwynck ◽  
Dominiek Maes ◽  
Maarten Hoogewijs ◽  
Dries Vercauteren ◽  
...  

Fibronectin (Fn) is a 440 kDa glycoprotein assumed to participate in sperm–egg interaction in human. Recently, it has been demonstrated that Fn – when present during bovine IVF – strongly inhibits sperm penetration. The present study was conducted firstly to evaluate the expression of Fn and its integrin receptor (α5β1) on male and female bovine gametes using indirect immunofluorescence and secondly, to determine the function of Fn during bovine IVF. Endogenous Fn was detected underneath the zona pellucida (ZP) and integrin α5 on the oolemma of cumulus-denuded oocytes. Bovine spermatozoa displayed integrin α5 at their equatorial segment after acrosome reaction. We established that the main inhibitory effect of exogenously supplemented Fn was located at the sperm–oolemma binding, with a (concurrent) effect on fusion, and this can probably be attributed to the binding of Fn to spermatozoa at the equatorial segment, as shown by means of Alexa Fluor 488-conjugated Fn. Combining these results, the inhibitory effect of exogenously supplemented Fn seemed to be exerted on the male gamete by binding to the exposed integrin α5β1 receptor after acrosome reaction. The presence of endogenous Fn underneath the ZP together with integrin α5 expression on oolemma and acrosome-reacted (AR) sperm cell surface suggests a ‘velcro’ interaction between the endogenous Fn ligand and corresponding receptors on both (AR) sperm cell and oolemma, initiating sperm–egg binding.


Blood ◽  
1980 ◽  
Vol 55 (4) ◽  
pp. 649-654
Author(s):  
AI Schafer ◽  
RW Alexander ◽  
RI Handin

There is evidence that platelet activation in the coronary circulation may be important in the pathogenesis of myocardial ischemia. Since organic nitrate vasodilators are commonly used in coronary artery disease, we have studied the in vitro effects of these drugs on platelet function. Nitroglycerin, isosorbide dinitrate, and their biotransformation product, inorganic nitrite, inhibited platelet aggregation with collagen, epinephrine, arachidonate, and ionophore, and blocked both primary and secondary aggregation in response to ADP. Nitroglycerin was studied in more detail. Its inhibitory effect was reversible and not dependent on external calcium concentration. It inhibited arachidonic acid oxygenation as measured by the arachidonate- induced oxygen burst and malonaldehyde production. These effects were not due to an increase in intracellular cyclic AMP. This unusual generalized inhibition of platelet function by nitroglycerin possibly contributes to its beneficial effect in myocardial ischemia in part by attenuating platelet reactivity in the coronary circulation.


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