title: Organ-specific testosterone-insensitive response of miRNA expression of C57BL/6 mice to Plasmodium chabaudi malaria.
abstract: Increasing evidence critically implicates miRNAs in the pathogenesis of diseases, but little is known in context with infectious diseases. This study investigates as to whether the testosterone-induced persistent susceptibility to blood-stage malaria of Plasmodium chabaudi coincides with changes in miRNA expression of the anti-malaria effectors sites spleen and liver. Female C57BL/6 mice were treated with vehicle or testosterone (T) for 3 weeks. Then, T treatment was discontinued for 12 weeks before challenge with 10(6) P. chabaudi-parasitized erythrocytes. The miRNA expression was examined after 12 weeks of T withdrawal and during infections at peak parasitemia on day 8 p.i. using miRXplore™ microarray technology. P. chabaudi infections induce an organ-specific response of miRNA expression. We can identify 25 miRNA species to be downregulated by more than 2-fold in the spleen and 169 miRNA species in the liver. Among these 194 miRNA species, there are 12 common miRNA species that are downregulated by 0.48-0.14-fold in both spleen and liver, which are miR-194, miR-192, miR-193A-3P, miR-145, miR-16, miR-99A, miR-99B, miR-15A, miR-152, let-7G, let-7B, and miR-455-3P. Only in the liver, there is an upregulation of the miR-142-5p by 2.5-fold and miR-342-3p by 5.1-fold. After 12 weeks of T withdrawal, the spleen exhibits only the miR-200A that is upregulated by 2.7-fold. In the liver, miR-376B, miR-493*, and miR-188-3P are upregulated by 2.4-fold, 2.2-fold, and 2.1-fold, respectively, and miR-347, miR-200A, and miR-200B are downregulated by approximately 0.4-fold. Upon infection, however, these changes are not sustained, i.e., the miRNA expressions of both spleen and liver of T-pretreated mice exhibit the same response to P. chabaudi malaria as that of vehicle-treated control mice. Our data suggest (1) that the P. chabaudi-induced downregulation of miRNA expression in spleen and liver is required to allow the upregulation of their numerous target genes in response to infection, and (2) that the T-induced persistent susceptibility to P. chabaudi does not affect the responsiveness of miRNA expression in spleen and liver to blood-stage malaria.
authors.affiliation: Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia. guraishi@yahoo.com
authors.forename: Saleh
authors.initials: S
authors.lastname: Al-Quraishy
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Dkhil
authors.forename: Denis
authors.initials: D
authors.lastname: Delic
authors.forename: Abdel Azeem
authors.initials: AA
authors.lastname: Abdel-Baki
authors.forename: Frank
authors.initials: F
authors.lastname: Wunderlich
mesh_terms: D000818:Animals; D005260:Female; D008099:Liver / Q000378:metabolism / Q000469:parasitology; D008288:Malaria / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D016788:Plasmodium chabaudi; D013047:Specific Pathogen-Free Organisms; D013154:Spleen / Q000378:metabolism / Q000469:parasitology; D013739:Testosterone / Q000494:pharmacology*
chemical_list: D035683:MicroRNAs; D013739:Testosterone