Table 1.

Hepatic MAT activity, levels of methionine cycle metabolites, and DNA methylation

Parameter	MAT1A+/+	MAT1A−/−
MAT activity, pmol/min/mg	31.89  ± 5.58	10.25  ± 1.63*
AdoMet, nmol/mg	0.19  ± 0.04	0.05  ± 0.02*
AdoHcy, nmol/mg	0.06  ± 0.02	0.07  ± 0.03
MTA, nmol/mg	0.10  ± 0.02	0.10  ± 0.03
GSH, nmol/mg	46.13  ± 5.97	27.82  ± 4.28*
GSSG, nmol/mg	4.23  ± 0.85	2.32  ± 0.3*
Overall DNA methylation†	1.00  ± 0.16	1.18  ± 0.16

Results represent mean ± SD from five or more animals each. Liver specimens were obtained from 3-month-old knockouts and wild-type littermates for determination of MAT activity, methionine cycle metabolites, and DNA methylation, as described in Methods. 

^*, P < 0.05 vs. wild-type littermates by the Kruskall–Wallis test. 

^† Overall DNA methylation measurements were normalized with respect to wild-type values. [³H]-dCTP incorporation in wild-type animals was 9,600 dpm/μg DNA.