Table 2. The rate of oxidative phosphorylation in SSM from young and aged mice with or without metformin treatment.

Mice	3 mo.		24 mo.
Groups	Vehicle (n=13)	Metformin (n=5)	Vehicle (n=11)	Metformin (n=5)
	Complex I substrates: glutamate + malate
State 3 (nAO/min/mg)	291±16	326±7	220±14*	243±13
State 4 (nAO/min/mg)	44±4	48±3	37±2	41±2
RCR	6.9±0.4	7.1±0.5	6.1±0.3	6.1±0.6
2 mM ADP (nAO/min/mg)	345±16	377±6	251±21*	272±25
	Complex II substrates: Succinate + rotenone
State 3 (nAO/min/mg)	642±25	587±24	557±20*	599±30
State 4 (nAO/min/mg)	179±8	172±8	149±5*	156±6
RCR	3.6±0.1	3.4±0.1	3.7±0.1	3.9±0.2
2 mM ADP (nAO/min/mg)	593±25	529±22	532±21	545±23

Mean ± SEM. *p<0.05 vs. 3 mo. Vehicle.