Figure 1.
Mean body weight from 11–22 weeks of age.
Autoimmune MRL/lpr mice were significantly lighter when compared to congenic controls. However, prolonged immunosuppression further reduced their body weight, but not in MRL +/+ mice.
Figure 2.
Daily fluid consumption from 11–22 weeks of age.
(A) Despite fluctuations in daily water intake over the course of the study, Veh MRL +/+ mice consumed the most water in the 2-bottle test. They also drank significantly more than their CY +/+ counterparts, a trend that was not noted in the MRL/lpr substrain. (B) Lacing sweetened solution with CY significantly reduced daily consumption. However, autoimmune MRL/lpr mice consumed significantly less CY solution in comparison to MRL +/+ mice, particularly after the first week of treatment.
Figure 3.
Although both substrains received similar CY dose at the starting of the treatment period, voluntary drinking in subsequent weeks was higher in less symptomatic MRL +/+ than in MRL/lpr mice.
Figure 4.
Weekly preference for sweet solutions.
Initially, CY lpr mice displayed a higher preference for CY/sucrose in comparison to control CY +/+ group at 11 weeks of age. However, this difference was transient and became the lowest of all groups by the end of the study.
Figure 5.
Behavioural effects of chronic exposure to CY/sucrose solution.
(A) Chronic immunosuppression reduced step-down latency in diseased MRL/lpr mice, but had the opposite effect on congenic controls. (B) In addition to the previously-documented substrain differences in sucrose consumption [24], CY had a significant detrimental effect on the performance in both groups. (C) Although a trend was noted, CY could not abolish previously-reported differences in overall floating in the forced swim test [23]. (D) Prolonged immunosuppression improved spontaneous ambulatory activity in MRL/lpr mice, but had a detrimental effect on MRL +/+ controls. (E) Conversely, CY exposure significantly improved (but did not normalize) running wheel activity in MRL/lpr mice.
Figure 6.
Immunosuppressive effects of continuous exposure to CY/sucrose solution.
Generalized immunosuppression in CY-exposed MRL/lpr mice evidenced by normalized spleen weight (A), as well as significant reductions in serum levels of autoantibodies directed towards dsDNA (B), cardiolipin (C), and PR3 (D) antigens.