α2u-globulins mediate manipulation of host attractiveness in Toxoplasma gondii–Rattus novergicus association

Abstract

Uninfected female rats (Rattus novergicus) exhibit greater attraction to the males infected with protozoan parasite Toxoplasma gondii. This phenomenon is contrary to the aversion towards infected males observed in multitude of other host-parasite associations. In this report, we describe a proximate mechanism for this anomaly. We demonstrate that T. gondii infection enhances hepatic production and urinary excretion of α2u-globulins in rats. We further demonstrate that α2u-globulins are sufficient to recapitulate male sexual attractiveness akin to effects of the infection. This manipulation possibly results in greater horizontal transmission of this parasite between the infected male and the uninfected female. It supports the notion that in some evolutionary niches parasites can alter host sexual signaling, likely leading to an increased rate of sexual transmission.

Parasitic manipulation of male sexual advertisement in Toxoplasma gondii- Rattus norvegicus association

“…In light of these observations on the role of testosterone in the fatal attraction hypothesis, I was interested how else Toxoplasma affects behavior of infected rats. As testosterone plays an important function in reproductive/sexual investment and behavior, this could explain the mate choice manipulation (96) and increased sexual advertisement observed (343).…”

“…Parasitism refers to the exploitative relationship between two species, where the parasite benefits at a cost for the host. In contrast to predators, parasites do not kill the host immediately and can cohabitate in their hosts for as long as years (1). Parasitism is widespread across kingdoms (with most animals serving as a host) and evolved convergently across phylogenies (2)(3)(4).…”

“…Such life cycles have evolved in parallel in numerous parasites from single simple life cycles (SLC) (13)(14)(15). In CLC, parasites have distinct morphological phases, which utilize different habitats or hosts (1,16). Trophic transmission is a common means of transfer between hosts where a definitive host predates upon the intermediate host (12).…”

“…With the creatinine levels, the samples were diluted to the lowest creatinine level in that batch of samples to be tested. Then protein was extracted via methanol and chloroform protocol1 and resuspended in PBS. The samples were then used for western blotting.…”

Toxoplasma gondii induced shift in decision making and impulsive behaviours in infected male rats (Rattus novergicus)

“…This increase is also supported by parallel evidence that biological substrates responsive to testosterone also change. This includes an increase in sexual pheromones produced by the liver and extra-hypothalamic arginine vasopressin in the brain [24,351]. These changes are known to reflect an increased supply of testosterone in rats.…”