Changes of Ghrelin/GOAT axis and mTOR pathway in the hypothalamus after sleeve gastrectomy in obese type-2 diabetes rats

Table 1 Changes in fasting blood glucose

Time points	Fasting blood glucose (mmol/L)
	S0	Sh	SG
First day	6.18 ± 1.19	5.89 ± 1.12	6.19 ± 0.94
Preoperative	15.03 ± 2.4a	15.9 ± 1.2a	15.88 ± 2.32a
Postoperative wk 8	14.55 ± 1.29	14.29 ± 1.69	9.00 ± 1.17ce

Statistical differences among the three groups were analyzed by one-way ANOVA followed by LSD-t and between two time points in one group using a paired t test.

^aP < 0.05, preoperative vs first day levels in the same group;

^cP < 0.05, postoperative vs preoperative levels in the SG group;

^eP < 0.05, SG vs S0 and Sh postoperatively. LSD: Least significant difference; Sh: Sham operation group; SG: Sleeve gastrectomy.

Table 2 Oral glucose tolerance test of blood glucose

Time points (min)	Blood glucose (mmol/L)
	First day			Preoperative			Postoperative
	S0	Sh	SG	S0	Sh	SG	S0	Sh	SG
0	6.18 ± 1.19	5.89 ± 1.12	6.19 ± 0.94	15.03 ± 2.40a	15.90 ± 1.20a	15.88 ± 2.32a	14.55 ± 1.29	14.29 ± 1.69	9.00 ± 1.17ce
15	6.18 ± 1.17	6.42 ± 1.22	6.66 ± 1.27	20.82 ± 3.80a	21.35 ± 4.13a	20.84 ± 4.41a	19.06 ± 2.68	18.39 ± 2.42	10.12 ± 1.07ce
30	7.15 ± 1.03	7.13 ± 1.27	7.03 ± 1.32	21.76 ± 3.45a	22.13 ± 2.96a	21.15 ± 2.86a	20.09 ± 4.02	22.47 ± 3.63	11.21 ± 1.02ce
60	7.22 ± 1.36	7.07 ± 1.38	6.93 ± 1.02	22.23 ± 3.47a	22.23 ± 4.03a	22.96 ± 2.78a	20.32 ± 3.26	19.80 ± 3.49	11.75 ± 0.95ce
90	6.45 ± 1.21	6.27 ± 1.31	6.58 ± 1.31	17.72 ± 2.19a	18.48 ± 2.54a	17.43 ± 2.61a	18.30 ± 2.50	18.81 ± 2.90	8.76 ± 1.01ce
120	6.00 ± 0.92	5.89 ± 0.65	5.58 ± 0.75	15.47 ± 1.55a	15.04 ± 1.58a	15.67 ± 1.44a	14.08 ± 1.00	15.07 ± 1.63	6.98 ± 1.13ce

Statistical differences among the three groups were analyzed by one-way ANOVA followed by LSD-t test and between two time points in one group using a paired t test.

^aP < 0.05, preoperative vs first day levels in the same group at the same time point;

^cP < 0.05, postoperative vs preoperative levels in the SG group;

^eP < 0.05, SG vs S0 and Sh postoperatively. LSD: Least significant difference; Sh: Sham operation group; SG: Sleeve gastrectomy.

Table 3 Oral glucose tolerance test of blood insulin

Time points (min)	Blood insulin (mU/L)
	First day			Preoperative			Postoperative
	S0	Sh	SG	S0	Sh	SG	S0	Sh	SG
0	13.06 ± 2.21	13.03 ± 2.01	12.97 ± 2.63	24.79 ± 3.06a	26.48 ± 2.19a	24.37 ± 2.51a	23.33 ± 1.81	27.58 ± 2.24	15.21 ± 2.87ce
15	19.16 ± 1.57	19.04 ± 1.83	20.63 ± 1.17	28.66 ± 3.20a	29.38 ± 3.33a	28.72 ± 2.39a	29.78 ± 2.86	32.95 ± 2.65	25.71 ± 7.73ce
30	40.90 ± 3.15	42.65 ± 9.89	41.64 ± 12.51	35.47 ± 3.36a	36.27 ± 3.21a	35.33 ± 4.68a	36.49 ± 3.25	36.78 ± 2.05	47.93 ± 3.31ce
60	63.46 ± 5.30	62.43 ± 6.01	65.38 ± 3.45	54.76 ± 2.85a	59.37 ± 2.12	59.81 ± 4.63a	57.36 ± 3.51	58.08 ± 2.77	69.05 ± 1.74ce
90	22.55 ± 1.80	21.81 ± 2.65	21.68 ± 3.23	80.35 ± 2.42a	82.68 ± 2.02a	80.68 ± 4.13a	79.79 ± 5.66	82.14 ± 3.46	30.55 ± 7.66ce
120	14.30 ± 1.82	13.25 ± 1.67	13.14 ± 2.02	66.15 ± 4.38a	70.11 ± 8.05a	71.52 ± 4.20a	71.26 ± 7.88	71.76 ± 6.63	18.23 ± 4.95ce

Statistical differences among the three groups were analyzed by one-way ANOVA followed by LSD-t and between two time points in one group using a paired t test.

^aP < 0.05, preoperative vs first day levels in the same group at the same time point;

^cP < 0.05, postoperative vs preoperative levels in the SG group;

^eP < 0.05, SG vs S0 and Sh postoperatively. LSD: Least significant difference; Sh: Sham operation group; SG: Sleeve gastrectomy.

Table 4 Hypothalamic mRNA expression of preproghrelin, ghrelin O-acyltransferase and neuropeptide Y

X-mRNA/β-acting-mRNA	S0	SG
Preproghrelin	0.63 ± 0.12	0.50 ± 0.11a
GOAT	0.96 ± 0.09	0.87 ± 0.08a
NPY	0.61 ± 0.04	0.65 ± 0.07

Hypothalamic mRNA expression of preproghrelin, GOAT and NPY was quantified using PCR and expressed as the ratio to the β-actin mRNA. Statistical differences between the two groups were analyzed using Student’s t test.

^aP < 0.05, S0 vs SG. GOAT: Ghrelin O-acyltransferase; SG: Sleeve gastrectomy; NPY: Neuropeptide Y.