Fig. 4

Age-related increases in IL-6 are also noted in multiple brain regions of BALB/cJ mice and Brown Norway Rats. Relative to young BALB/cJ mice, old BALB/cJ mice express significantly higher levels of IL-6 protein in the A ventral hippocampus (VHIPP; effect of age across sexes indicated by the bar extended across the male and female histograms), B dorsal hippocampus (DHIPP), C prefrontal cortex (PFC), D striatum, and E cerebellum. Similarly, old Brown Norway Rats showed higher expression of IL-6 protein relative to young rats in the F PFC and G cerebellum, with females expressing higher levels than males in the cerebellum across ages. These data suggest widespread age-related increases in IL-6 expression are conserved across species and are not tied to a single rearing environment. Data expressed as mean ±SEM. Brightness and contrast of blots and Ponceau stain (PS). images adjusted for graphical clarity. *Main effect of age (vs. young), P=0.002 to <0.001; @main effect of sex (vs. male), P=0.002. Y—young, O—old