1 research outputs found
Ependymal damage in a Plasmodium yoelii yoelii lethal murine malaria model
Malaria continues to be a major global health
problem, and over 40% of the world’s population is at
risk. Severe or complicated malaria is defined by clinical
or laboratory evidence of vital organ dysfunction,
including dysfunction of the central nervous system
(CNS). The pathogenesis of complicated malaria has not
been completely elucidated; however, the development
of the multiorgan affection seems to play an important
role in the disruption of the blood brain barrier (BBB)
that protects the CNS against chemical insults.
Historically, the BBB has received more attention in the
pathogenesis of malaria than have the cerebrospinal
fluid-brain barrier (CSFBB) and ependymal cells. This
perspective may be misguided because, in the context of
disease or toxicity, the CSFBB is more vulnerable to
many foreign invaders than are the capillaries. Given the
lack on studies of the damage to the CSFBB and
ependymal epithelium in experimental murine malaria,
the present study evaluated morphological changes in
the ependymal cells of CD-1 male mice infected with
lethal Plasmodium yoelii yoelii (Pyy) via histopathology
and scanning electron microscopy (SEM). Samples were
taken two, four and six days post-infection (PI). No
lesions were observed upon the initial infection. By the
fourth day PI, fourth ventricle ependymal samples
exhibited disruptions and roughened epithelia. More
severe injuries were observed at six days PI and included
thickened cilia and deep separations between the
ependymal intercellular spaces. In some of the analyzed
areas, the absence of microvilli and cell layer
detachment were observed, and some areas exhibited
blebbing surfaces. The ependymal cell lesions observed
in the CD1 male mice infected with lethal Pyy seemed to
facilitate the paracellular permeability of the CSFBB and
consequently promote the access of inflammatory
mediators and toxic molecules through the barrier, which
resulted in damage to the brain tissue. Understanding the
mechanism of ependymal disruption during lethal
murine malaria could help to elucidate the local and
systemic factors that are involved in the pathogenesis of
the disease and may provide essential clues for the
prevention and treatment of complicated human malaria