(b).

Group	n	RBP4 (ng/mL)	HOMA-IR	HOMA-β	25(OH)D (nmol/L)	Weight
NC	8	13.58 ± 3.56	1.85 ± 0.36	80.25 ± 9.47	130.00 ± 10.34	430.00 ± 32.36
DM1	10	18.61 ± 4.89∗	3.97 ± 1.13∗	56.24 ± 7.61∗	108.00 ± 8.15∗	480.00 ± 35.63∗
DM2	11	25.34 ± 5.47∗▲	6.27 ± 2.56∗▲	42.84 ± 6.82∗▲	97.00 ± 7.72∗	530.00 ± 47.84∗▲
DM3	12	20.89 ± 4.76∗★	4.54 ± 1.21∗★	51.04 ± 7.73∗★	450.00 ± 38.59∗▲★	520.00 ± 45.19∗▲
F		9.721	12.121	37.487	664.27	10.97
P		<0.001	<0.001	<0.001	<0.001	<0.001

^∗ P < 0.05 versus NC group. ^▲P < 0.05 versus DM1 group. ^★P < 0.05 versus DM2 group. RBP4: retinol-binding protein 4; HOMA-IR: homeostasis model assessment of insulin resistance; HOMA-β: homeostasis model assessment β-cell function index; 25(OH)D: 25-hydroxyvitamin D.