Figure 6.

Activation of the glycolytic system and inactivation of the TCA cycle in axons after axotomy. a, c, e, g, Representative cross-section images of immunohistochemistry for glycolytic enzyme (a: HK-1, c: PFK-1, e: LDHA, g: LDHB) before and 2 d after axotomy. The axonal fluorescence intensity in the dashed line was measured. b, d, f, h, The axonal fluorescence intensity of HK-1 (b), PFK-1 (d), LDHA (f), and LDHB (h; n = 3 mice per group). HK-1, PFK1, and LDHA fluorescence intensity was significantly increased after axotomy, whereas LDHB was significantly decreased. i, k, m, Representative images of immunohistochemistry for TCA cycle enzyme (i: PDH-E1α, k: CS, m: IDH3A) before and after axotomy. The axonal fluorescence intensity in the dashed line was measured. j, l, n, The axonal fluorescence intensity of PDH-E1α (j), CS (k), and IDH3A (n; n = 3 mice per group). PDH-E1α, CS, and IDH3A fluorescence intensity was significantly decreased after axotomy. All histologic evaluations were performed 3 mm distal to the sectional end and corresponding uninjured nerve. Error bars indicate SD scale bar, 10 μm. *p < 0.05, **p < 0.01, ***p < 0.001, two-tailed t test. CS, citrate synthase; IDH, isocitrate dehydrogenase; HK, hexokinase; LDHA, lactate dehydrogenase A subunit lactate; LDHB, lactate dehydrogenase B subunit lactate; dehydrogenase; PFK, phosphofructokinase; PDH, pyruvate dehydrogenase; TCA cycle, tricarboxylic acid cycle.