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Mature microRNAs (miRNAs) are small, non-coding regulatory RNAs which can elicit post-transcriptional repression of mRNA levels of target genes. Here, we report the identification of 67 mature and 42 precursor miRNAs in the Schistosoma mansoni parasite. The evolutionarily conserved S. mansoni miRNAs consisted of 26 precursor miRNAs and 35 mature miRNAs, while we identified 16 precursor miRNAs and 32 mature miRNAs that displayed no conservation. These S. mansoni miRNAs are located on seven autosomal chromosomes and a sex (W) chromosome. miRNA expansion through gene duplication was suggested for at least two miRNA families miR-71 and mir-2. miRNA target finding analysis identified 389 predicted mRNA targets for the identified miRNAs and suggests that the sma-mir-71 may be involved in female sexual maturation. Given the important roles of miRNAs in animals, the identification and characterization of miRNAs in S. mansoni will facilitate novel approaches towards prevention and treatment of Schistosomiasis.

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The immune response in the skin of dogs infected with Leishmania chagasi and its association with distinct levels of tissue parasitism and clinical progression of canine visceral leishmaniasis (CVL) are poorly understood and limited studies are available. A detailed analysis of the profiles of cytokines (IFN-γ, IL-4, IL-5, IL-10, IL-12, IL-13, TGF-β1 and TNF-α) and transcription factors (T-bet, GATA-3 and FOXP3) in the skin of 35 naturally infected dogs was carried out using real-time PCR alongside determinations of skin parasite density and the clinical status of CVL. A mixed cytokine profile with high levels of expression of IFN-γ, TNF-α and IL-13 was determined in asymptomatic dogs. Additionally, the levels of transcription factors GATA-3 and FOXP3 were correlated with the asymptomatic disease. A mixed cytokine profile was also observed during active CVL. Moreover, high levels of IL-10 and TGF-β1, concomitant with the low expression of IL-12, may represent a key condition that allows persistence of parasite replication in the skin. The results obtained indicate that in asymptomatic disease or lower levels of skin parasite density, a mixed inflammatory, regulatory immune response profile may be of major relevance for both the maintenance of the clinical status of the dogs as well as for parasite persistence and replication at low levels.

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Long noncoding RNAs (lncRNAs) are transcripts generally longer than 200 nucleotides with no or poor protein coding potential, and most of their functions are also poorly characterized. Recently, an increasing number of studies have shown that lncRNAs can be involved in various critical biological processes such as organism development or cancer progression. Little, however, is known about their effects in helminths parasites, such as Schistosoma mansoni. Here, we present a computational pipeline to identify and characterize lncRNAs from RNA-seq data with high confidence from S. mansoni adult worms. Through the utilization of different criteria such as genome localization, exon number, gene length, and stability, we identified 170 new putative lncRNAs. All novel S. mansoni lncRNAs have no conserved synteny including human and mouse. These closest protein coding genes were enriched in 10 significant Gene Ontology terms related to metabolism, transport, and biosynthesis. Fifteen putative lncRNAs showed differential expression, and three displayed sex-specific differential expressions in praziquantel sensitive and resistant adult worm couples. Together, our method can predict a set of novel lncRNAs from the RNA-seq data. Some lncRNAs are shown to be differentially expressed suggesting that those novel lncRNAs can be given high priority in further functional studies focused on praziquantel resistance.

The mitochondrial uncoupling proteins (UCPs) of interscapular brown adipose tissue (iBAT) and of muscles play important roles in energy balance. For instance, the expression of UCP1 and UCP3 are modulated by free fatty acid gradients induced by high-sugar diets and acute exercise that is dependent on sympathetic stimulation. However, the effects of endurance training in animals fed with high-sugar diets are unknown. This study aims to evaluate the long-term effects of diet and exercise on UCP1 and UCP3 levels and energy balance efficiency. Rats fed with standard or high-sugar (HSD) diets were simultaneously subjected to running training over an 8-week period. After the training period, the rats were decapitated, and the iBAT and gastrocnemius muscle tissues were removed for evaluation of the β₃-receptor, Ucp1, and Ucp3 mRNA and protein expression, which were analyzed by quantitative reverse transcriptase polymerase chain reaction and Western blot, respectively. Groups fed with an HSD displayed a higher adiposity index and iBAT weight (P < .05), whereas exhibited an up-regulation of Ucp1 mRNA and protein levels (P < .05). Training increased β₃-receptor mRNA in iBAT and reduced the Ucp3 mRNA in muscle tissues. In association with an HSD, training restored the increasing β₃-receptor mRNA and greatly up-regulated the levels of Ucp3 mRNA. Therefore, training blocked the HSD-induced up-regulation of UCP1 expression in iBAT, whereas it up-regulated the expression of Ucp3 mRNA in muscle. These results suggest that training enhances the relationship between Ucp1/Ucp3 mRNA levels, which could result in higher energy efficiency, but not when HSD-induced elevated sympathetic activity is maintained.