Fig. 1

KD treatment specifically increases type I NRG1 expression in the hippocampus. A Experimental design. After 1 week of habituation, male adult mice were divided into two groups, fed with a control diet (CD) or KD for different time as indicated. Hippocampal tissues were collected and subjected to western blotting. B increased expression of NRG1 and phosphorylated ErbB4 (P-ErbB4) proteins in the hippocampus of mice fed with KD. Shown were representative blots. GAPDH served as the loading control. C Quantitative analysis of NRG1 expression in D. One-way ANOVA with sidak’s multiple comparison tests. For CD group, F_(4,10) = 0.5538, P = 0.7011; For KD group, F_(4,10) = 17.79, P = 0.0002. 1 week vs 0 week, P = 0.0459; 2 week vs 0 week, P = 0.0073; 3 week vs 0 week, P = 0.0001; 4 week vs 0 week, P = 0.0002. D Quantitative analysis of ErbB4 expression in D. One-way ANOVA with sidak’s multiple comparison tests. For CD group, F_(4,10) = 2.662, P = 0.0954; For KD group, F_(4,10) = 2.922, P = 0.077. E Quantitative analysis of P-ErbB4/ErbB4 levels in D. One-way ANOVA with sidak’s multiple comparison tests. For CD group, F_(4,10) = 0.5962, P = 0.6737; For KD group, F_(4,10) = 7.929, P = 0.0038. 1 week vs 0 week, P = 0.8158; 2 week vs 0 week, P = 0.1382; 3 week vs 0 week, P = 0.0055; 4 week vs 0 week, P = 0.0049. F Diagram of Nrg1 gene structure. Type-specific forward primers (indicated by arrows) for each type were located in unique exons, whereas reverse primers were located in either Ig or EGF domain. G Increased type I Nrg1 mRNA level in the hippocampus of KD-fed mice. Two-way ANOVA with sidak’s multiple comparison tests. F_(1,30) = 24.89, P < 0.0001; For type I, P < 0.0001; for type II, P = 0.8537; for type III, P = 0.9973. * indicates p < 0.05; ** indicates p < 0.01; *** indicates p < 0.001