ePoster Presentation
Biography
rnNimanthi Jayathilaka earned her Ph.D. from the University of Southern California and conducted her postdoctoral studies at the University of California, San Diego. Currently, she serves as a Senior Lecturer in Chemistry at the University of Kelaniya, Sri Lanka. Her primary research interest is transcriptional regulation in communicable and non-communicable diseases. rn
Abstract
Dengue is mosquito-borne disease characterized by a mild febrile illness as dengue fever (DF) and severe stage of illness as dengue hemorrhagic fever (DHF) and dengue shock syndrome that can lead to mortality. Early clinical management is critical in preventing mortality. Virus-induced activation of phagocytes is associated with oxidative stress. Several markers of oxidative stress have been reported to differentiate between DF and DHF. This study was carried out to assess the potential of biochemical markers of oxidative stress; nitric oxide (NO) and oxidized LDL (Ox LDL) to serve as markers of disease severity during the early stages of infection. We assessed the levels of NO and Ox LDL in both plasma and saliva due to the potential of salivary biomarkers to serve as a non-invasive prognostic tool. Plasma and saliva samples collected within 4 days from fever onset were analyzed. Griess reaction was used to quantify plasma and salivary NO levels. Plasma NO concentration in the DF group (n= 36) was significantly higher than that of those who later developed DHF (n=31) (p<0.05). Although salivary NO concentration in DF (n=16) and DHF groups (n=18) also show a difference, there was a high standard deviation of data probably due to the influence of oral health and diet. Plasma and saliva Ox LDL in DF and DHF groups were analyzed using ELISA. Plasma Ox LDL concentration in DF (n= 16) was higher than that of DHF groups (n=16), while salivary Ox LDL in DF patients (n=8) was significantly higher (p<0.05) than that of DHF patients (n=8). Therefore, the plasma NO levels and salivary Ox LDL may serve as reliable biomarkers of the severity of Dengue infection during the acute phase.
Biography
Julia A Loos has a PhD in Biological Science (National University of Mar del Plata, 2017) and she is currently working as a postdoc under the direction of Prof. Dr. Andrea Cumino. She has been serving as assistant teacher for subjects such as Histology, General Microbiology and Pharmacology that are part of the Biology, Biochemistry and Medicine courses of study. She participates in several research projects on Parasitology and has published original articles. Currently, her research is focused on the study of intermediary metabolism and energy control in the larval stage of Echinococcus spp.
Abstract
We have previously shown that Metformin (Met), an anti-hyperglycemic and anti-proliferative drug, exhibits considerable in vitro and in vivo activity against E. granulosus metacestodes. Here, we extended the study and demonstrated that the drug also possess chemopreventive properties against alveolar echinococcosis in mice. As drug administration was shown to induce the Eg-AMPK activation, its anti-echinococcal effects might be a consequence of cellular energy charge depletion in the parasite. Based on this and the fact that only one FoxO transcription factor is present in the genome of Echinococcusspp, the aim of this work is investigate the activation state of FoxO and its relation with the expression of genes encoding sirtuins and key autophagy-related proteins in parasites incubated under both control and energy-stress conditions. Eg-FoxO sequence reveals several post-translationally modifiable residues highly conserved. By in totoimmunolocalization assays, we detected the expression and subcellular localization of a phosphorylated (Ser352) and an acetylated (Lys373) form of Eg-FoxO in control and Met-treated protoscoleces. Interestingly, similar expression patterns were observed in both samples. Additionally, by qPCR analysis, we found that Met produced an increase in the transcriptional expression of sirt and/or atg genes in E. granulosus protoscoleces and metacestodes and in E. multilocularis primary cells. In this regards, BLASTn analysis of the upstream sequences in putative promoters of several of these genes showed the conserved binding motif described for FoxO-activated genes. These results suggest a possible role of FoxO in the transcriptional regulation of Echinococcus spp. under energy stress conditions. We also detected expression of Atg8 polypeptide (LC3) with both a diffuse and punctate staining in control and Met-treated E. granulosus protoscoleces and E. multilocularis vesicles. However, western blot analysis demonstrated higher levels of Eg-Atg8-PE (LC3-II) in Met-treated protoscoleces, suggesting a possible induction of autophagy under this condition. Altogether, our data indicate that FoxO, Sirt and autophagy might participate in the regulation of Met-stimulated energy stress in Echinococcus spp.