Evaluation of in silico, in vitroα-amylase inhibition potential and antidiabetic activity of Pterospermum acerifolium bark

Figures & data

Figure 1. Comparison of binding mode of β-sitosterol in the active site pocket of human pancreatic α-amylase.

Figure 2. Hydrogen bond interactions between β-sitosterol and aminoacid residues in the active site pocket of human pancreatic α-amylase.

Figure 3. Hydrogen bond interactions between acarbose and aminoacid residues in the active site pocket of human pancreatic α-amylase.

Table 1. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on changes in blood glucose level during OGTT.

	Blood glucose level (mg/dl)
Treatment	0 min	30 min	60 min	120 min
Normal control	75.77 ± 0.48	120.20 ± 1.24	114.80 ± 2.10	81.83 ± 2.242
Diabetic control	345.80 ± 6.79^aaaa	452.00 ± 3.20^aaaa	444.30 ± 6.38^aaaa	401.80 ± 5.15^aaaa
PABEF-1	239.20 ± 13.85	297.70 ± 17.48	282.80 ± 17.60	255.80 ± 6.86
PABEF-2	221.00 ± 7.79	277.80 ± 8.55	259.80 ± 7.15	248.20 ± 6.23
PABE1-1	238.70 ± 13.29	288.50 ± 10.14	272.50 ± 10.34	260.70 ± 13.66
PABE1-2	228.00 ± 11.12	282.50 ± 14.43	262.50 ± 15.22	244.70 ± 11.82
PABE2-1	282.80 ± 8.92^aa	343.80 ± 7.60^aa	338.70 ± 5.68^aaa	332.50 ± 7.58^aaa
PABE2-2	287.70 ± 9.40^aaa	341.50 ± 9.17^aa	337.20 ± 10.14^aaa	330.50 ± 11.78^aaa
PABE3-1	216.80 ± 16.51	267.00 ± 11.74^b	245.00 ± 10.19^b	227.00 ± 11.62^b
PABE3-2	211.20 ± 10.77^b	265.70 ± 9.68^b	237.00 ± 9.28^b	222.70 ± 11.61^b
STD drug	191.00 ± 11.62^bb	240.50 ± 12.83^bb	209.20 ± 12.27^bbb	195.20 ± 11.52^bbb

The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001, ^aap < 0.01 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Table 2. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on changes in blood glucose level.

	Blood glucose (mg/dl)
Treatment	Day 0	Day 14	Day 21	Day 28
Normal control	68.00 ± 1.07	75.17 ± 0.48	74.17 ± 0.40	77.00 ± 0.37
Diabetic control	286.50 ± 9.52	342.50 ± 5.81^aaaa	373.30 ± 7.84^aaaa	424.50 ± 5.15^aaaa
PABEF-1	296.30 ± 11.57	241.30 ± 13.75	240.50 ± 17.86^a	188.50 ± 11.60
PABEF-2	285.70 ± 9.39	222.50 ± 8.09	198.20 ± 13.90	177.50 ± 8.07
PABE1-1	301.50 ± 11.14	240.30 ± 13.43	212.70 ± 11.46	177.70 ± 8.72
PABE1-2	298.30 ± 10.40	230.00 ± 13.43	196.70 ± 11.96^b	175.80 ± 13.51
PABE2-1	297.30 ± 9.52	285.00 ± 8.93^aa	290.80 ± 8.10^aaa	282.80 ± 9.70^aaa
PABE2-2	303.00 ± 10.44	289.00 ± 9.56^aaa	277.80 ± 11.50^aaa	276.30 ± 9.69^aaa
PABE3-1	295.80 ± 10.53	217.50 ± 16.53^b	181.70 ± 15.96^b	161.70 ± 14.59^b
PABE3-2	298.70 ± 9.35	213.70 ± 10.73^bb	174.70 ± 12.58^bb	151.50 ± 11.95^bb
STD drug	297.20 ± 10.42	193.00 ± 11.44^bbb	145.20 ± 12.23^bbb	117.80 ± 12.03^bbb

The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001, ^aap < 0.01, ^ap < 0.05 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Table 3. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on body weight changes and glycosylated Hb.

	Body weight (g)
Treatment	Initial	Final	Glycosylated Hb (%)
Normal control	196.80 ± 3.64	238.10 ± 4.04	2.74 ± 0.26
Diabetic control	195.70 ± 4.96	150.40 ± 4.91	7.93 ± 0.72^aaaa
PABEF-1	198.20 ± 5.36	202.60 ± 5.02	6.19 ± 0.03
PABEF-2	195.30 ± 4.49	200.30 ± 5.02	6.09 ± 0.16
PABE1-1	197.90 ± 3.75	201.40 ± 3.73	5.77 ± 0.05
PABE1-2	201.70 ± 2.16	208.90 ± 2.41	5.47 ± 0.03
PABE2-1	200.90 ± 4.57	174.70 ± 4.56	7.01 ± 0.08^aaa
PABE2-2	200.10 ± 2.39	187.00 ± 1.77	6.75 ± 0.08^aa
PABE3-1	200.40 ± 3.29	205.60 ± 3.05	5.35 ± 0.04^b
PABE3-2	197.20 ± 3.50	222.30 ± 4.11	4.97 ± 0.05^bb
STD drug	199.00 ± 4.37	227.00 ± 3.88	3.32 ± 0.08^bbb

The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001, ^aap < 0.01 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Table 4. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on levels of serum liver enzymes.

Treatment	ALT (IU/L)	AST (IU/L)	ALP (IU/L)
Normal control	25.83 ± 0.27	31.92 ± 0.22	11.97 ± 0.22
Diabetic control	54.74 ± 0.50^aaaa	72.30 ± 0.40^aaaa	27.27 ± 0.09^aaaa
PABEF-1	46.53 ± 0.03	61.34 ± 0.33	24.41 ± 0.07
PABEF-2	43.62 ± 0.48	59.29 ± 0.34	22.21 ± 0.05
PABE1-1	38.82 ± 0.22	58.64 ± 0.46	21.51 ± 0.09
PABE1-2	38.04 ± 0.24^b	56.43 ± 0.34^b	20.28 ± 0.08
PABE2-1	50.33 ± 0.38^aaaa	71.17 ± 0.48^aaaa	27.53 ± 0.05^aaaa
PABE2-2	51.41 ± 0.38^aaa	68.91 ± 0.27^aaa	26.44 ± 0.04^aa
PABE3-1	37.52 ± 0.41	46.85 ± 0.24^b	18.21 ± 0.05
PABE3-2	34.80 ± 0.23^bb	44.43 ± 0.37^bb	16.61 ± 0.07^bb
STD drug	28.93 ± 0.23^bbb	36.95 ± 0.21^bbb	14.18 ± 0.03^bbb

The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001, ^aap < 0.01 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Table 5. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on levels of lipid parameters.

Treatment	Triglycerides (mg/dl)	Totalcholesterol (mg/dl)	HDL-C (mg/dl)
Normal control	91.64 ± 0.52	57.35 ± 0.40	59.37 ± 0.40
Diabetic control	215.60 ± 1.47^aaaa	163.40 ± 3.66^aaaa	14.35 ± 0.36^aaaa
PABEF-1	144.60 ± 1.02	106.00 ± 0.51	33.78 ± 0.48
PABEF-2	139.90 ± 1.06	103.80 ± 0.56	35.13 ± 0.66
PABE1-1	136.30 ± 0.89	102.80 ± 0.46	35.38 ± 0.34
PABE1-2	131.10 ± 0.85^b	98.77 ± 0.4^b	37.45 ± 0.43^b
PABE2-1	197.90 ± 1.50^aaaa	148.70 ± 0.47^aaaa	21.35 ± 0.37^aaaa
PABE2-2	192.20 ± 1.60^aaa	144.40 ± 0.42^aaa	24.39 ± 0.35^aaa
PABE3-1	115.90 ± 1.14^bb	82.13 ± 6.65^b	46.80 ± 0.53^b
PABE3-2	106.20 ± 1.20^bbb	77.83 ± 0.53^bb	48.90 ± 0.49^bb
STD drug	127.50 ± 1.08^b	65.79 ± 0.57^bbb	52.45 ± 0.34^bbb

The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Table 6. Effect of ethyl acetate fraction and subfractions of Pterospermum acerifolium bark on levels of antioxidant status.

Treatment	TBARS	Catalase	Red.Glutathione	SOD
Normal control	0.98 ± 0.19	74.82 ± 3.67	49.16 ± 1.96	7.86 ± 0.89
Diabetic control	1.74 ± 0.78^aaaa	30.78 ± 3.16^aaaa	24.17 ± 2.07^aaaa	3.7 ± 0.35^aaaa
PABEF-1	1.45 ± 0.36	47.32 ± 2.71^a	34.81 ± 1.87^a	4.32 ± 0.16^a
PABEF-2	1.39 ± 0.12	51.33 ± 1.73	36.06 ± 2.11	4.67 ± 0.32
PABE1-1	1.39 ± 0.81	50.16 ± 3.34	35.41 ± 1.32	4.53 ± 0.16
PABE1-2	1.35 ± 0.87	55.31 ± 1.77	36.11 ± 1.81	4.86 ± 0.31
PABE2-1	1.69 ± 0.32^aaa	30.74 ± 2.17^aaaa	27.33 ± 1.82^aaa	3.8 ± 0.16^aaa
PABE2-2	1.67 ± 0.18^aa	33.21 ± 1.61^aaa	29.11 ± 2.11^aa	3.93 ± 0.22^aa
PABE3-1	1.18 ± 0.32^b	56.81 ± 1.32	38.11 ± 1.09^b	5.86 ± 0.21^b
PABE3-2	1.14 ± 0.03^bb	59.31 ± 1.72^b	40.81 ± 1.12^bb	6.01 ± 0.11^bb
Std Drug	1.05 ± 0.17^bbb	68.87 ± 2.16^bbb	44.86 ± 2.07^bbb	6.41 ± 0.09^bbb

Thio barbituricacid reactive substances (TBARS) expressed as nM of MDA/mg protein; Catalase expressed as nmoles of H₂O₂ consumed/min/mg protein; Superoxide dismutase (SOD) expressed as U/mg protein; Glutathione expressed as µg of GSH/mg protein. The results are expressed as mean ± standard error of the mean (SEM). p Values of ^aaaap < 0.0001, ^aaap < 0.001, ^aap < 0.01, ^ap < 0.05 were compared with normal control. p Values of ^bbbp < 0.001, ^bbp < 0.01, ^bp < 0.05 were compared with disease control.

Figure 4. Histopathological observation of experimental rats pancreas after 30 days of treatment (A) normal control; (B) diabetic control; (C) diabetic animals treated with PABEF (400 mg/kg); (D) diabetic animals treated with PABE1 (30 mg/kg); (E) diabetic animals treated with PABE2 (30 mg/kg); (F) diabetic animals treated with PABE3 (30 mg/kg); (G) diabetic animals treated with glibenclamide (600 µg/kg).