. Author manuscript; available in PMC: 2015 Dec 30.

Published in final edited form as: Free Radic Biol Med. 2003 Nov 1;35(9):1064–1072. doi: 10.1016/s0891-5849(03)00468-4

Table 2.

Age-Associated Changes in Mitochondrial Thioredoxin and GSH-Related Enzymes

	Young		Old

	IFM	SSM	IFM	SSM
Thioredoxin reductase (nmol/min/mg protein)	13.61 ± 2.14	11.98 ± 1.61	11.33 ± 1.16	24.78 ± 2.80
GSSG reductase (nmol/min/mg protein)	19.28 ± 0.86^*	19.32 ± 2.16	12.99 ± 0.91^*^†	20.30 ± 2.00^†
Glutaredoxin reductase (nmol/min/mg protein)	7.02 ± 0.77^*	6.46 ± 0.49	3.96 ± 0.44^*^†	6.78 ± 1.11^†

Values are expressed as mean ± SEM. Activities of mitochonchondrial thioredoxin, glutaredoxin, and GSSG reductase in IFM and SSM from young and old rats were measured as described in Materials and Methods. The results show a significant age-related loss in both GSH and glutaredoxin reductase activity in IFM isolated from old vs. young animals. In contrast, thioredoxin reductase activity in IFM did not show any significant loss with age. Moreover, thioredoxin reductase activity increased by 2-fold in SSM isolated from old animals. The results are expressed as mean ± SEM.

denotes significant (p < .05) difference between identical mitochondrial preparations from young and old rats, and

^†

denotes differences between IFM and SSM within the same age group.