Table 1.

Body and liver weights, plasma ALT and AST levels as well as markers of glucose homeostasis in blood and liver in female mice fed a C diet or WSD with or without Arg supplementation for 6 weeks

	Diet groups				P (2-factor ANOVA)1
	C	WSD	C+Arg	WSD+Arg	DExAE	AE	DE
Caloric intake (kcal/mouse/day)	10 ± 0.1a	10 ± 0.2a	10 ± 0.1a	10 ± 0.1a	NS	NS	NS
Weight gain (g)	2.2 ± 0.2a	1.7 ± 0.2a	2.3 ± 0.3a	1.5 ± 0.4a	NS	NS	0.02
Absolute weight (g)	20.5 ± 0.4a	20.4 ± 0.2a	20.0 ± 0.5a	20.6 ± 0.6a	NS	NS	NS
Liver weight (g)	1.0 ± 0.1b	1.2 ± 0.0a	0.9 ± 0.0b	1.2 ± 0.0a	NS	NS	<0.01
Liver to body weight ratio (%)	5.0 ± 0.1b	6.0 ± 0.1a	4.7 ± 0.1b	5.7 ± 0.2a	NS	NS	<0.01
Plasma ALT (U/L)	16 ± 1.0a	23 ± 3.2a	16 ± 0.7a	20 ± 3.8a	NS	NS	NS
Plasma AST (U/L)	41 ± 1.9a	49 ± 4.2a	40 ± 1.7a	50 ± 4.5a	NS	NS	0.02
Blood glucose (mg/dL)	74 ± 5b,c	93 ± 5a,b	104 ± 5a	71 ± 5c	<0.01	NS	NS
Hepatic Ir mRNA (% of control)	100 ± 11a	105 ± 7a	103 ± 8a	111 ± 11a	NS	NS	NS
Hepatic Irs-1 mRNA (% of control)	100 ± 17a,b	125 ± 24a	84 ± 16a,b	50 ± 6b	NS	<0.01	NS

Values represent mean ± SEM

Means without a common letter differ, P < 0.05. NS P ≥ 0.05

ALT alanine aminotransferase, AST aspartate aminotransferase, Arg arginine, C control, Ir insulin receptor, Irs-1 insulin receptor substrate 1, WSD Western-style diet, DExAE interaction between diet and arginine, AE arginine effect, DE diet effect

¹Homogeneity of the variances was not significant (P > 0.05)