Disclosing Ribose-5-Phosphate Isomerase B Essentiality in Trypanosomatids.

Ribose-5-phosphate isomerase (RPI) belongs to the non-oxidative branch of the pentose phosphate pathway, catalysing the inter-conversion of D-ribose-5-phosphate and D-ribulose-5-phosphate. Trypanosomatids encode a type B RPI, whereas humans have a structurally unrelated type A, making RPIB worthy of exploration as a potential drug target. Null mutant generation in Leishmania infantum was only possible when an episomal copy of RPIB gene was provided, and the latter was retained both in vitro and in vivo in the absence of drug pressure. This suggests the gene is essential for parasite survival. Importantly, the inability to remove the second allele of RPIB gene in sKO mutants complemented with an episomal copy of RPIB carrying a mutation that abolishes isomerase activity suggests the essentiality is due to its metabolic function. In vitro, sKO promastigotes exhibited no defect in growth, metacyclogenesis or macrophage infection, however, an impairment in intracellular amastigotes' replication was observed. Additionally, mice infected with sKO mutants rescued by RPIB complementation had a reduced parasite burden in the liver. Likewise, Trypanosoma brucei is resistant to complete RPIB gene removal and mice infected with sKO mutants showed prolonged survival upon infection. Taken together our results genetically validate RPIB as a potential drug target in trypanosomatids.We would like to thank Professor Ana Tomás from the Institute for Molecular and Cell Biology, University of Porto, Portugal, for providing LimTXNPx antibody; Dr. Paul Michels from Université Catholique de Louvain, Belgium, for providing Tbenolase antibody; Professor Graham Coombs, Strathclyde University, Glasgow, for LmCS antibody; Professor Buddy Ullman, School of Medicine, Oregan Health and Science University, USA, for LdHGPRT antibody; Dr. Christine Clayton, Zentrum fur Molekulare Biologie der Universitat Heidelberg, Germany, for TbAldolase antibody. We would also like to thank Professor Jeremy Mottram, University of Glasgow, for pGL345HYG and Professor Marc Ouellette, Centre de Recherche en Infectiologie, of Laval University, Canada, for pSPαNEOα and pSPαBLASTα. We would also like to thank Dr. Jane MacDougall from Photeomix, France, for proofreading the English of the manuscript. The research leading to these results has received funding from the European Community’s Seventh Framework Programme under grant agreement No. 602773 (Project KINDRED).’ The COST Action CM1307: Targeted chemotherapy towards diseases caused by endoparasites has also contributed for this work. We would like to acknowledge Fundação para a Ciência e Tecnologia (FTC) for supporting Joana Faria (SFRH/BD/79712/2011) and Inês Loureiro (SFRH/BD/64528/2009). Inês Loureiro was also supported by the European Community’s Seventh Framework Programme (KINDRED-PR300102-BD). JT is an Investigator FCT funded by National funds through FCT and co-funded through European Social Fund within the Human Potential Operating Programme. Nuno Santarem and Pedro Cecílio are supported by fellowships from the European Community’s Seventh Framework Programme under grant agreements No. 602773 (Project KINDRED) and No. 603181 (Project MuLeVaClin), respectively

Pilot evaluation of HEAL – A natural experiment to promote obesity prevention behaviors among low-income pregnant women

Instituting interventions during the prenatal period is optimal for early obesity prevention in the child. Healthy Eating Active Living (HEAL) is a six-week, multi-component program to promote breastfeeding, healthy dietary habits, cooking skills and physical activity among Medicaid-eligible pregnant-women in Texas. HEAL is integrated into the healthcare system and offered as a standard-of-care for eligible patients. Methods: Preliminary evaluation of this natural experiment conducted from March 2015 through October 2016 informs the initial feasibility, acceptability and effects of the program on participant diet, home nutrition environment, physical activity, and breastfeeding self-efficacy and intentions measured using self-report surveys. Analysis of covariance (ANCOVA) was conducted to evaluate pre- and post-intervention changes, controlling for participants' ethnicity, age, and income level. Interaction effects of session attendance on the outcomes were further assessed. Results: Of the 329 women who enrolled in HEAL, 210 women completed the pre-post assessment (64% retention rate). Pre-to-post intervention, there were significant increases in availability and intake of fruits and vegetables, self-efficacy towards consuming more fruits and vegetables, and cooking frequency and skills (p < 0.05), and decreased frequency of eating heat and serve foods (p < 0.05). Significant improvements in physical activity, duration of breastfeeding, perceived benefits and intentions to breastfeed were also observed (p < 0.05). Higher attendance of HEAL sessions was associated with better outcomes. Process evaluation demonstrated 95% fidelity of program implementation. Conclusion: HEAL operationalizes clinic-community linkages and shows promise in improving behaviors during pregnancy. Future research warrants the use of a stringent study design with a control group to determine program efficacy. Keywords: Pregnancy, Obesity prevention, Nutrition, Breastfeeding, Physical activit