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Echeverry, M. C.

Publications and source records attributed to Echeverry, M. C..

2 recordsLinked to original sources

AKT-like kinase promotes cell survival during nutritional stress in tripanosomatids

Tritryps are protozoan parasites that belong to the Trypanosomatidae family, which encompasses the etiologic agents of leishmaniasis, African and American trypanosomiasis. These parasites undergo different stress conditions across their life cycle, such as nutritional stress, which needs to be deadened in order to guarantee the survival of the parasite inside its vector and mammal hosts. Here we show that the lack of the serine threonine kinase PKB / AKT-like function, either by allosteric inhibition of its Plekstrin domain (PH) in T. cruzi, the reduction of the gene transcripts in T. brucei by RNAi assays, or by AKT-like gene knockout in L. major, reduce the tolerance to nutritional stress of parasites that triggers apoptosis-like events, including DNA fragmentation, mitochondrial damage and loss of plasma membrane integrity. Additionally, we observed that double knockout of Akt-like in L. major impairs its infective capacity. This work confirms some of the previously described functions regarding parasite survival for AKT-like kinases in the Leishmania genus. The present work also provides strong evidence of the probable function of Akt-like in T. cruzi and T. brucei survival and infectivity. Author summaryEndemic countries for neglected tropical diseases are called to play a paramount role in the discovery of new drug candidates through the application of new drug development strategies. Rational drug design method have proven to be compatible with the development of new drug for orphan and neglected diseases since it substantially reduces the costs of discovery and development, a desirable condition for public funded initiatives. Previously we have identified a new parasite protein kinase (AKT-like) as promising new target candidate by means of computational tools and probed its biological role in trypanosomatids. Here we show that inhibition of the AKT-like kinase in trypanosomatids by different approaches (chemical inhibition, interference RNA and gene knockout) decreases the fitness and survival of the parasites in vitro, interfering with the capacity of the parasites to react and survive stress conditions similar to those experienced by the cell in the natural life cycle. Additionally our results strongly supports the potential of a new family of compounds previously described by bioinformatics means as potential trypanocidal agents. Altogether we show that the specific inhibition of the AKT-like is a promising strategy for the further development of anti-trypanosome drugs.

microbiology↗

Toward an objective diagnostic for detection of Leishmania RNA virus (LRV) in clinical samples from cutaneous leishmaniasis patients.

Leishmania RNA virus (LRV) is a double strand RNA virus belonging to the Totiviridae family detected as cytoplasmic inclusions in some strains of the human parasite Leishmania spp. Experimental evidence supports the hypothesis that human co-infection with Leishmania spp-LRV triggers an exacerbated immune response in the host that can be responsible for the observed complicated outcomes in cutaneous leishmaniasis (CL), such as mucosal leishmaniasis (ML) and treatment failure of cutaneous leishmaniasis (TFCL). However, the reported frequencies of LRV associated to complicated outcomes in patients series are highly variable, diminishing the relevance on the virus presence in the pathogenesis of the disease. For determining if the apparent inconsistent information about the frequency of LRV associated to CL complicated outcomes could be connected with the virus detection approach, this study tested previously described methods for LRV detection in clinical samples of patients according with the type of sample. In 36 samples with diagnosis of complicated forms of CL (15 ML, 21 TFCL) and 6 samples with non-Leishmania spp infection, LRV presence was assessed by RT-PCR, RT-qPCR and nested-PCR.\n\nBy combining methods, LRV1 presence was confirmed in 45% (9/20) of isolates and 75% (12/16) of biopsies. The predominant LRV1-infected Leishmania species in this study was Leishmania (Viannia) braziliensis and, for first time, Leishmania (Viannia) panamensis was found infected in clinical samples. In a number of cases, LRV1 was undetectable in the isolates but present in their respective biopsies, suggesting the possibility of underreporting of LRV1 presence in studies focused in parasites isolates exclusively.

microbiology↗