Fig. 2: Asymptomatic HSV-1 brain infection and EAE, individually or combined, increase the mRNA levels of senescence-associated genes in the spinal cord.

Mice were mock-treated (healthy group, white bars with circles) or asymptomatically infected with HSV-1 strain 17syn⁺ in the brain (HSV-1 group, orange bars with triangles). EAE was induced 4 weeks after mock treatment (EAE group, blue bars with diamonds), or infection (HSV-1-EAE group, purple bars with squares). Spinal cord homogenates were recovered 14 days after EAE induction, or 45–50 days after HSV-1 infection, or mock treatment alone. The expression of senescence-associated genes was evaluated at the mRNA level by RT-qPCR using the 2^−ΔΔCTmethod with β-actin as a reference gene. a Heatmap comparing mRNA levels of senescence-associated genes in the spinal cord of HSV-1, EAE, and HSV-1-EAE groups. The orange color indicates upregulation while the blue color indicates downregulation. Darker colors indicate stronger effects. Relative mRNA expression of the gene products b Hmgb-1, c Pdrg1, d Cdkn1a, e Cdkn2a, f Lmnb1, g Timp1, h Mmp12, i Ccl2, j Cxcl2, and k Il6 in the different mouse groups compared to healthy controls. Values represent means ± SEM of two independent experiments (n = 7 animals/group). Log-transformed data were analyzed using one-way ANOVA followed by Dunnett’s post-hoc test; ***p < 0.001, **p < 0.01, and *p < 0.05.