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PLoS Neglected Tropical Diseases Jul 2024When two species hybridize, the two parental genomes are brought together and some alleles might interact for the first time. To date, the extent of the transcriptomic...
When two species hybridize, the two parental genomes are brought together and some alleles might interact for the first time. To date, the extent of the transcriptomic changes in first hybrid generations, along with their functional outcome constitute an important knowledge gap, especially in parasite species. Here we explored the molecular and functional outcomes of hybridization in first-generation hybrids between the blood fluke parasites Schistosoma haematobium and S. bovis. Through a transcriptomic approach, we measured gene expression in both parental species and hybrids. We described and quantified expression profiles encountered in hybrids along with the main biological processes impacted. Up to 7,100 genes fell into a particular hybrid expression profile (intermediate between the parental expression levels, over-expressed, under-expressed, or expressed like one of the parental lines). Most of these genes were different depending on the direction of the parental cross (S. bovis mother and S. haematobium father or the reverse) and depending on the sex. For a given sex and cross direction, the vast majority of genes were hence unassigned to a hybrid expression profile: either they were differentially expressed genes but not typical of any hybrid expression profiles or they were not differentially expressed neither between hybrids and parental lines nor between parental lines. The most prevalent profile of gene expression in hybrids was the intermediate one (24% of genes assigned to a hybrid expression profile). These results suggest that transcriptomic compatibility between S. haematobium and S. bovis remains quite high. We also found support for an over-dominance model (over- and under-expressed genes in hybrids compared to parental lines) potentially associated with heterosis. In females in particular, processes such as reproductive processes, metabolism and cell interactions as well as signaling pathways were indeed affected. Our study hence provides new insight on the biology of Schistosoma hybrids with evidences supporting compatibility and heterosis.
PubMed: 38954732
DOI: 10.1371/journal.pntd.0012267 -
Parasite (Paris, France) 2024Schistosomiasis is of medical and veterinary importance. Despite the critical situation of schistosomiasis in sub-Saharan Africa, few molecular epidemiological studies...
Schistosomiasis is of medical and veterinary importance. Despite the critical situation of schistosomiasis in sub-Saharan Africa, few molecular epidemiological studies have been carried out to determine the role of animals in its transmission. In Mali, it has been over three decades since the last molecular study of animal schistosomes was carried out. It is now urgent to identify circulating strains of the parasite because of potential interactions with other schistosome species, which could complicate disease control. The aim of our work was to study the composition and genetic structure of schistosome populations collected from cattle. The prevalence of schistosome was 23.9%, with the prevalences of Schistosoma bovis (Sb) and S. curassoni (Sc) estimated at 12.6% and 9.8%, respectively. No hybrid strains or S. haematobium were found. The parasites displayed distinct geographical distribution with Sb dominant in Bamako (78.8% and 98% in Central Bamako Slaughterhouse and Sabalibougou Slaughterhouses, respectively) and Sc dominant in Kayes (95.3%). Of the 476 parasites with a complete genetic profile, 60.4% were pure Sc, and were mainly from Kayes. We identified two clusters at the site level (Fst of 0.057 and 0.042 for Sb and Sc, respectively). Cluster 1 was predominantly composed of pure Sb parasites and cluster 2 was mainly composed of pure Sc parasites, from Bamako and Kayes, respectively. Our study shows that cattle schistosomiasis remains endemic in Mali with S. bovis and S. curassoni. A robust genetic structure between the different schistosome populations was identified, which included two clusters based on the geographical distribution of the parasites.
Topics: Animals; Cattle; Mali; Schistosoma; Cattle Diseases; Schistosomiasis; Prevalence; Genetic Variation; Genetics, Population; DNA, Helminth
PubMed: 38953782
DOI: 10.1051/parasite/2024035 -
Frontiers in Immunology 2024Schistosomiasis (SM) is a parasitic disease caused by . SM causes chronic inflammation induced by parasitic eggs, with collagen/fibrosis deposition in the granuloma...
INTRODUCTION
Schistosomiasis (SM) is a parasitic disease caused by . SM causes chronic inflammation induced by parasitic eggs, with collagen/fibrosis deposition in the granuloma process in the liver, spleen, central nervous system, kidneys, and lungs. Pulmonary arterial hypertension (PAH) is a clinical manifestation characterized by high pressure in the pulmonary circulation and right ventricular overload. This study investigated the production of functional autoantibodies (fAABs) against the second loop of the G-protein-coupled receptor (GPCR) in the presence of hepatic and PAH forms of human SM.
METHODS
Uninfected and infected individuals presenting acute and chronic manifestations (e.g., hepatointestinal, hepato-splenic without PAH, and hepato-splenic with PAH) of SM were clinically evaluated and their blood was collected to identify fAABs/GPCRs capable of recognizing endothelin 1, angiotensin II, and a-1 adrenergic receptor. Human serum was analyzed in rat cardiomyocytes cultured in the presence of the receptor antagonists urapidil, losartan, and BQ123.
RESULTS
The fAABs/GPCRs from chronic hepatic and PAH SM individuals, but not from acute SM individuals, recognized the three receptors. In the presence of the antagonists, there was a reduction in beating rate changes in cultured cardiomyocytes. In addition, binding sites on the extracellular domain functionality of fAABs were identified, and IgG1 and/or IgG3 antibodies were found to be related to fAABs.
CONCLUSION
Our data suggest that fAABs against GPCR play an essential role in vascular activity in chronic SM (hepatic and PAH) and might be involved in the development of hypertensive forms of SM.
Topics: Autoantibodies; Humans; Animals; Receptors, G-Protein-Coupled; Rats; Male; Female; Adult; Hypertension, Pulmonary; Middle Aged; Myocytes, Cardiac; Schistosomiasis mansoni; Schistosoma mansoni; Schistosomiasis
PubMed: 38953035
DOI: 10.3389/fimmu.2024.1404384 -
Parasites & Vectors Jun 2024Reliance on praziquantel for the treatment and control of schistosomiasis is likely to facilitate the emergence of drug resistance. Combination therapy targeting adult... (Randomized Controlled Trial)
Randomized Controlled Trial
Efficacy and safety of single-dose artesunate plus sulfalene/pyrimethamine combined with praziquantel for the treatment of children with Schistosoma mansoni or Schistosoma haematobium in western Kenya: a randomised, open-label controlled trial.
BACKGROUND
Reliance on praziquantel for the treatment and control of schistosomiasis is likely to facilitate the emergence of drug resistance. Combination therapy targeting adult and juvenile schistosome worms is urgently needed to improve praziquantel efficacy and delay the potential development of drug resistance. We assessed the efficacy and safety of single-dose praziquantel combined with single-dose artesunate plus sulfalene-pyrimethamine in the treatment of Kenyan children with schistosomiasis.
METHODS
This was an open-label, randomised clinical trial involving 426 school-aged children (7-15 years old) diagnosed with Schistosoma mansoni (by Kato-Katz) or S. haematobium (by urine filtration). They were randomly assigned (1:1:1) to receive a single dose of praziquantel (40 mg/kg), a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate) or combination therapy using a single dose of praziquantel (40 mg/kg) combined with a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate). The primary outcome was cure and egg reduction rates at 6 weeks post-treatment in the available case population. Adverse events were assessed within 3 h after treatment.
RESULTS
Of the 426 children enrolled, 135 received praziquantel, 150 received artesunate plus sulfalene-pyrimethamine, and 141 received combination therapy. Outcome data were available for 348 (81.7%) children. For S. mansoni-infected children (n = 335), the cure rates were 75.6%, 60.7%, and 77.8%, and the egg reduction rates were 80.1%, 85.0%, and 88.4% for praziquantel, artesunate plus sulfalene-pyrimethamine, and combination therapy, respectively. For S. haematobium-infected children (n = 145), the corresponding cure rates were 81.4%, 71.1%, and 82.2%, and the egg reduction rates were 95.6%, 97.1%, and 97.7%, respectively. Seventy-one (16.7%) children reported mild-intensity adverse events. The drugs were well tolerated and no serious adverse events were reported.
CONCLUSIONS
A single oral dose of praziquantel combined with artesunate plus sulfalene-pyrimethamine cured a high proportion of children with S. haematobium but did not significantly improve the treatment efficacy for either urinary or intestinal schistosomiasis. Sequential administration of praziquantel and artesunate plus sulfalene-pyrimethamine may enhance the efficacy and safety outcomes.
Topics: Humans; Child; Praziquantel; Pyrimethamine; Animals; Adolescent; Artesunate; Female; Male; Schistosomiasis mansoni; Schistosoma haematobium; Schistosomiasis haematobia; Schistosoma mansoni; Drug Therapy, Combination; Kenya; Artemisinins; Treatment Outcome; Anthelmintics; Sulfalene; Drug Combinations; Parasite Egg Count
PubMed: 38943214
DOI: 10.1186/s13071-024-06359-6 -
Scientific Reports Jun 2024Poor birth outcomes in low- and middle income countries are associated with maternal vitamin D deficiency and chronic helminth infections. Here, we investigated whether...
Poor birth outcomes in low- and middle income countries are associated with maternal vitamin D deficiency and chronic helminth infections. Here, we investigated whether maternal Schistosoma haematobium affects maternal or cord vitamin D status as well as birth outcomes. In a prospective cross-sectional study of pregnant women conducted in Lambaréné, Gabon, we diagnosed maternal parasitic infections in blood, urine and stool. At delivery we measured vitamin D in maternal and cord blood. S. haematobium, soil-transmitted helminths, and microfilariae were found at prevalences of 30.2%, 13.0%, and 8.8%, respectively. Insufficient vitamin D and calcium levels were found in 28% and 15% of mothers, and in 11.5% and 1.5% of newborns. Mothers with adequate vitamin D had lower risk of low birthweight babies (aOR = 0.11, 95% CI 0.02-0.52, p = 0.01), whilst offspring of primipars had low cord vitamin D levels, and low vitamin D levels increased the risk of maternal inflammation. Maternal filariasis was associated with low calcium levels, but other helminth infections affected neither vitamin D nor calcium levels in either mothers or newborns. Healthy birth outcomes require maintenance of adequate vitamin D and calcium levels. Chronic maternal helminth infections do not disrupt those levels in a semi-rural setting in sub-Saharan Africa.
Topics: Humans; Pregnancy; Female; Infant, Newborn; Adult; Pregnancy Complications, Parasitic; Vitamin D; Helminthiasis; Vitamin D Deficiency; Cross-Sectional Studies; Pregnancy Outcome; Young Adult; Prospective Studies; Prevalence
PubMed: 38937587
DOI: 10.1038/s41598-024-65232-9 -
Frontiers in Public Health 2024Baseline mapping showed that schistosomiasis was highly/moderately endemic in nine districts in Sierra Leone. Mass drug administration (MDA) with praziquantel started in...
BACKGROUND
Baseline mapping showed that schistosomiasis was highly/moderately endemic in nine districts in Sierra Leone. Mass drug administration (MDA) with praziquantel started in 2009, and after multiple rounds of treatment, an impact assessment was conducted in 2016 followed by a second re-assessment in 2022 using cluster sampling to provide more granular data for refining chiefdom (sub-district) treatment strategies.
METHODS
On average, 20 rural villages were systematically selected per district by probability proportional to population size across the nine districts. Surveys were conducted in schools, and 24 school children aged between 5 and 14 years were randomly selected, with an equal number of boys and girls. One stool sample and one urine sample were collected per child. Two Kato-Katz slides were examined per stool for infection. Hemastix strips were used as a proxy for infection with urine filtration used for egg counts on hematuria-positive samples.
RESULTS
In total, 4,736 stool samples and 4,618 urine samples were examined across 200 schools in 125 chiefdoms. Overall, the prevalence of was 16.3% (95% CI: 15.3-17.4%), while the overall prevalence of was 2.0% (95% CI: 1.6-2.4%) by hematuria. The prevalence of heavy infections for and was 1.5% (95% CI: 1.1-1.9%) and 0.02% (95% CI: 0.0-0.14%), respectively. Among 125 chiefdoms surveyed, the overall schistosomiasis prevalence was <10% in 65 chiefdoms, 10-49.9% in 47 chiefdoms, and ≥ 50% in 13 chiefdoms. There was a mixed relationship between schistosomiasis in school children and WASH access in schools.
CONCLUSION
Sierra Leone has made significant progress in reducing schistosomiasis prevalence across the country after a decade of MDA intervention. However, high prevalence remains in some hotspot chiefdoms. The next steps are for the national program to investigate and address any potential issues such as low coverage or poor knowledge of schistosomiasis risk behaviors and, where appropriate, consider broadening to community-wide treatment in hotspot chiefdoms or communities.
Topics: Humans; Sierra Leone; Child; Female; Male; Adolescent; Child, Preschool; Praziquantel; Feces; Animals; Mass Drug Administration; Prevalence; Anthelmintics; Schistosomiasis; Schistosoma mansoni; Schistosomiasis mansoni; Rural Population; Endemic Diseases; Cluster Analysis; Schistosoma haematobium
PubMed: 38932788
DOI: 10.3389/fpubh.2024.1415486 -
Microorganisms Jun 2024Serine protease inhibitors are a superfamily of proteins that regulate various physiological processes including fibrinolysis, inflammation and immune responses. In...
Serine protease inhibitors are a superfamily of proteins that regulate various physiological processes including fibrinolysis, inflammation and immune responses. In parasite systems, serpins are believed to play important roles in parasite colonization, inhibition of host immune serine proteases and penetration of defensive barriers. However, serpins are less well characterized in schistosomes. In this study, a serpin (Smserpin-p46) containing a 1360 base pair open reading frame, was cloned, expressed and functionally characterized. Bioinformatics analysis revealed that Smserpin-p46 contains the key residues, structural domains and motifs characteristic of inhibitory serpins. Gene expression profiling demonstrated stage-specific expression of with the highest expression in adult male worms. Recombinant Smserpin-p46 (rSmserpin-p46) inhibited both human neutrophil cathepsin G and elastase, key serine proteases involved in NETosis, a program for the formation of neutrophil extracellular traps. Using specific rabbit antiserum, Smserpin-p46 was detected in soluble worm antigen preparation and was localized to the adult worm tegument. Cumulatively, the expression of Smserpin-p46 on the parasite tegument and its ability to inhibit proteases involved in NETosis highlights the importance of this serpin in parasite-host interactions and encourages its further investigation as a candidate vaccine antigen for the control of schistosomiasis.
PubMed: 38930546
DOI: 10.3390/microorganisms12061164 -
PloS One 2024Schistosomiasis is a neglected tropical disease which imposes a considerable and enduring impact on affected regions, leading to persistent morbidity, hindering child...
Schistosomiasis is a neglected tropical disease which imposes a considerable and enduring impact on affected regions, leading to persistent morbidity, hindering child development, diminishing productivity, and imposing economic burdens. Due to the emergence of drug resistance and limited management options, there is need to develop additional effective inhibitors for schistosomiasis. In view of this, quantitative structure-activity relationship studies, molecular docking, molecular dynamics simulations, drug-likeness and pharmacokinetics predictions were applied to 39 Schistosoma mansoni Thioredoxin Glutathione Reductase (SmTGR) inhibitors. The chosen QSAR model demonstrated robust statistical parameters, including an R2 of 0.798, R2adj of 0.767, Q2cv of 0.681, LOF of 0.930, R2test of 0.776, and cR2p of 0.746, confirming its reliability. The most active derivative (compound 40) was identified as a lead candidate for the development of new potential non-covalent inhibitors through ligand-based design. Subsequently, 12 novel compounds (40a-40l) were designed with enhanced anti-schistosomiasis activity and binding affinity. Molecular docking studies revealed strong and stable interactions, including hydrogen bonding, between the designed compounds and the target receptor. Molecular dynamics simulations over 100 nanoseconds and MM-PBSA free binding energy (ΔGbind) calculations validated the stability of the two best-designed molecules. Furthermore, drug-likeness and pharmacokinetics prediction analyses affirmed the potential of these designed compounds, suggesting their promise as innovative agents for the treatment of schistosomiasis.
Topics: Molecular Docking Simulation; Molecular Dynamics Simulation; Drug Design; Schistosoma mansoni; Ligands; Animals; Schistosomiasis; Quantitative Structure-Activity Relationship; NADH, NADPH Oxidoreductases; Humans; Multienzyme Complexes
PubMed: 38923997
DOI: 10.1371/journal.pone.0302390 -
Tropical Medicine and Infectious Disease May 2024snails surviving drought play a key role in the seasonal transmission of urogenital schistosomiasis, although our knowledge of their adaptation to dry season is still...
snails surviving drought play a key role in the seasonal transmission of urogenital schistosomiasis, although our knowledge of their adaptation to dry season is still limited. We investigated the survival dynamic and infestation by the of snails during the dry and rainy seasons in a single pond in an area of seasonal schistosomiasis transmission in Senegal. During the rainy season, 98 (94.23%) and six (5.76%) were collected, respectively. In the dry season, outnumbered , but all five (100%) collected were viable and alive after the interruption of aestivation by immersion in water, while only 7 of 24 (29.16%) collected emerged from their dormant state. The rate of infestation with during the rainy season was 18.2% (19/104), while all the viable snails collected during the dry season were negative. and have different seasonal dynamics with no evidence of maintaining infestation during the drought. Further studies including more survey sites and taking account both snails biology and ecological conditions are needed to better understand snail adaptation to seasonal changes and their ability to maintain infestation during drought.
PubMed: 38922033
DOI: 10.3390/tropicalmed9060121 -
Pathogens (Basel, Switzerland) Jun 2024The expansion of drug resistant parasites sheds a serious concern on several neglected parasitic diseases. Our recent results on cancer led us to envision the use of...
The expansion of drug resistant parasites sheds a serious concern on several neglected parasitic diseases. Our recent results on cancer led us to envision the use of peptide-alkoxyamines as a highly selective and efficient new drug against schistosome adult worms, the etiological agents of schistosomiasis. Indeed, the peptide tag of the hybrid compounds can be hydrolyzed by worm's digestive enzymes to afford a highly labile alkoxyamine which homolyzes spontaneously and instantaneously into radicals-which are then used as a drug against Schistosome adult parasites. This approach is nicely summarized as . Several hybrid peptide-alkoxyamines were prepared and clearly showed an activity: two of the tested compounds kill 50% of the parasites in two hours at a concentration of 100 µg/mL. Importantly, the peptide and alkoxyamine fragments that are unable to generate alkyl radicals display no activity. This strong evidence validates the proposed mechanism: a specific activation of the prodrugs by the parasite proteases leading to parasite death through in situ alkyl radical generation.
PubMed: 38921780
DOI: 10.3390/pathogens13060482