Table 1.

Cystatin B deficiency disrupts cerebellar redox homeostasis at 6 months of age

Redox assayCerebellum
Cystatin B+/+Cystatin B−/−p value*
SODa (units/mg protein)632.1 ± 35.8482.4 ± 20.6<0.05
GSHb (nmol/mg tissue)1.8 ± 0.0041.0 ± 0.142<0.05
GSSG:GSHc0.061 ± 0.0030.085 ± 0.006<0.05
8-epi PGF2αd (pg/mg)1.0 ± 0.095.6 ± 1.1<0.005
Glutathione peroxidasee (units/mg protein)24.4 ± 1.830.1 ± 1.3<0.05
  • *p values are determined by Student's t test. In the last column, p values corresponding to the following redox analyses are compared as follows.

  • aOne unit of SOD activity (units per milligrams of protein) is defined as 50% inhibition of formazan production. SOD activity was significantly reduced in Cystatin B−/− cerebella compared with wild-type controls [n = 5 (+/+), n = 4 (−/−)].

  • bGSH was significantly reduced in Cystatin B−/− cerebella compared with wild-type controls [n = 4 (+/+), n = 4 (−/−)].

  • cGSSG:GSH was significantly increased in Cystatin B−/− cerebella compared with wild-type controls [n = 4 (+/+), n = 4 (−/−)].

  • dLipid peroxidation was assayed based on competition between 8-epi–PGF2α and an 8-epi–PGF2α-acetylcholinesterase conjugate. Lipid peroxidation was significantly increased in Cystatin B−/− cerebella compared with wild-type controls [n = 3 (+/+), n = 5 (−/−)].

  • eGlutathione peroxidase activity was assayed by NADPH oxidation. Glutathione peroxidase activity increased significantly in Cystatin B−/− cerebella compared with wild-type controls [n = 3 (+/+), n = 5 (−/−)].