Analysis of sex differences in dietary copper-fructose interaction-induced alterations of gut microbial activity in relation to hepatic steatosis

Table 1 Effects of dietary fructose and marginal copper deficiency on metabolic phenotypes in male rats

Variable	CuA (n = 7)	CuAF (n = 8)	CuM (n = 7)	CuMF (n = 8)	P value of factors (two-way ANOVA)
Body weight (BW, g)	347 ± 20.6	346.4 ± 19.6	351.7 ± 24.5	346.2 ± 16.8	NS
BW gain (g)	287.9 ± 18.9	285.4 ± 19	291.6 ± 23.1	285.9 ± 18.5	NS
Liver weight (LW, g)	13.07 ± 0.8	13.71 ± 0.79	12.31 ± 1.25	13.15 ± 2.14	NS
LW/BW (%)	3.763 ± 0.115	3.958 ± 0.131	3.501 ± 0.241^#	3.783 ± 0.438	Cu, p = 0.0357 F, p = 0.0228
White adipose weight (WAT, g)	3.949 ± 0.383	4.149 ± 0.897	3.347 ± 0.25	3.831 ± 0.529	Cu, p = 0.0408
WAT/BW (%)	1.14 ± 0.13	1.19 ± 0.199	0.953 ± 0.048	1.107 ± 0.152	Cu, p = 0.0176
Energy efficiency ratio (EER, %)	7.78 ± 0.51	6.87 ± 046*	7.98 ± 0.63^#	6.85 ± 0.44*^$	F, p < 0.0001
Cecum weight (g)	2.736 ± 0.366	2.528 ± 0.276	2.909 ± 0.294	2.718 ± 0.202	NS
Food consumption (g/rat/day)	17.58 ± 2.88	13.93 ± 2.04*	17.36 ± 3.13	14.06 ± 2.07*	F, p = 0.0007
Water intake (ml/rat/day)	26.18 ± 6.31	53.63 ± 17.01*	24.52 ± 5.86^#	53.73 ± 20.79*^$	F, p < 0.0001
Energy intake (Kcal/rat/day)	66.11 ± 10.81	74.13 ± 12.30	65.26 ± 12.77	74.52 ± 13.50	NS
Plasma TG (mg/dL)	49.01 ± 13.26	95.08 ± 53.56*	36.83 ± 10.66^#	91.86 ± 25.76^$	F, p = 0.0002
Plasma cholesterol (mg/dL)	53.28 ± 20.19	53.43 ± 23.13	52.58 ± 13.94	41.73 ± 24.4	NS
Plasma NEFA (μM)	203.6 ± 49.3	400.5 ± 144.7*	263.1 ± 97.4	273.8 ± 64.6	F, p = 0.0073 Cu x F, p = 0.0149
Plasma glucose (mg/dL)	104.9 ± 18.8	147.3 ± 23.7*	119 ± 14.2	129.9 ± 16.4^#	F, p = 0.0012 Cu x F, p = 0.0394

Male and female weanling Sprague-Dawley rats from the Harlan Laboratories (Indianapolis, IN) were fed (ad lib) a modified AIN-93G purified rodent diet with defined copper content in the form of cupric carbonate for 8 weeks. The copper content is 6 mg/kg in an adequate copper diet (DYET# 115612) and 1.5 mg/kg in a marginal copper deficient diet (DYET# 115581), respectively. Animals had free access to either deionized water or deionized water containing 10% fructose (w/v) as the only drink during the 8-week experiment. The animals were single housed in stainless steel cages rinsed with EDTA in a temperature and humidity-controlled room with a 12:12-h light–dark cycle. Data are expressed as means ± SD (n = 7–8) and analyzed by two-way ANOVA testing factors of copper (Cu), fructose (F), and interactions (Cu × F), followed by Tukey’s multiple comparison test. Statistical significance was set to p ≤ 0.05. P values are displayed for the factors Cu, F, and Cu × F. NS, p > 0.05. * versus CuA; ^# versus CuAF; ^$ versus CuM
CuA adequate copper diet, CuM marginal copper deficient diet, CuAF adequate copper diet +10% fructose drinking, CuMF marginal copper deficient diet +10% fructose drinking, TG triglyceride, NEFA nonesterified fatty acids

ISSN: 2042-6410