Morphological, biochemical, transcriptional and epigenetic responses to fasting and refeeding in intestine of Xenopus laevis

Table 1 Morphological changes of small intestines and biochemical changes of plasma parameters in fed, fasted and refed Xenopus laevis

	Fed group	Fasted group		Refed group
	22 days	22 days	5 months	1 day after
	22 days	22 days	5 months	21 days fasting
Sample number of group (n)	8	8	6	8
Body weight (g)
Start of experiment	51.10 ± 2.74	51.39 ± 1.32	53.75 ± 3.01	52.69 ± 1.33
End of experiment	55.03 ± 3.05	48.30 ± 1.13	45.75 ± 3.10	49.65 ± 1.94
Intestine
Wet weight (g)	0.54 ± 0.06^a	0.28 ± 0.01^b	0.22 ± 0.01	0.41 ± 0.03^c
Length (cm)	5.50 ± 0.34	4.80 ± 0.29	5.05 ± 0.38	5.21 ± 0.32
Diameter (mm)	2.64 ± 0.27	2.21 ± 0.12	1.87 ± 0.07	2.40 ± 0.14
Outer diameter of mucosa/submucosa layer (mm)	2.26 ± 0.29	1.76 ± 0.10	1.45 ± 0.08	2.01 ± 0.09
Circumference of epitherial layer (mm)	35.01 ± 4.26^a	19.83 ± 1.67^b	13.88 ± 2.18	24.52 ± 4.22^{a, b}
Muscularis externa width (mm)	0.19 ± 0.02	0.22 ± 0.02	0.21 ± 0.01	0.20 ± 0.03
Number of goblet cells/mm	68.12 ± 4.21	55.06 ± 13.42	48.2 ± 3.95	49.15 ± 9.69
Protein content (mg/g wet whight)	114.5 ± 7.02	102.8 ± 9.88	Not determined	99.41 ± 8.16
Number of throughs in a villus-trough unit	4.64 ± 0.88^a	2.77 ± 0.43^a	2.71 ± 0.19	7.97 ± 1.43^b
Total troughs/section	62.25 ± 6.23^a	30.42 ± 5.55^b	26.11 ± 2.68	80.96 ± 7.45^a
Blood
Glucose (mg/dL)	44.55 ± 4.08^a	28.38 ± 5.35^b	41.52 ± 3.71	31.02 ± 3.25^b
Triglyceride (mg/dL)	242.19 ± 51.82^a	107.45 ± 14.30^b	65.33 ± 16.15	141.00 ± 18.89^{a, b}
Cholesterol (mg/dL)	173.97 ± 27.99	120.57 ± 16.44	141.00 ± 26.91	122.00 ± 13.80
Free fatty acid (mEq/L)	0.93 ± 0.08^a	0.49 ± 0.05^b	0.35 ± 0.06	0.62 ± 0.12^b

Values presented are mean ± SEM (n = 8). Different letters (a, b and c) indicate significant differences between the groups (p < 0.05)
The data of the fasted group for 5 months are excluded from the statistical analysis