Effects of butanol fraction of Ziziphus mucronata root ethanol extract on glucose homeostasis, serum insulin and other diabetes-related parameters in a murine model for type 2 diabetes

Figures & data

Figure 1. The effects of oral treatment of butanol fraction of Z. mucronata root on feed and fluid intakes of type 2 diabetic rats. Data are presented as the mean ± SD of eight animals. ^a–bValues with different letters over the bars for a given parameter are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).

Figure 2. The effects of oral treatment of butanol fraction of Z. mucronata root on mean body weight gain of type 2 diabetic rats. Data are presented as the mean ± SD of eight animals. ^a–bValues with different letters for a given week are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).

Figure 3. Weekly blood glucose concentrations (post induction) of different animal groups. Data are presented as the mean ± SD of eight animals. ^a–dValues with different letters for a given week are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).

Figure 4. Oral glucose tolerance test (OGTT) for all groups of animals in the last week of experimental period. Data are presented as the mean ± SD of eight animals. ^a–cValues with different letters for a given time are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).

Table 1. Serum insulin and fructosamine concentrations, indices of hepatic and renal damage as well as computed HOMA-IR and HOMA-β scores for different animal groups at the end of the experimental period.

	NC	DBC	DZL	DZH	DMF	NZT
Insulin (pmol/L)	153.12 ± 9.91^bc	64.20 ± 29.93^a	148.24 ± 33.04^b	131.37 ± 35.10^b	119.19 ± 13.00^b	165.73 ± 18.96^bc
Fructosamine (μmol/L)	196.33 ± 5.57^a	258.40 ± 10.92^ab	258.60 ± 19.15^ab	234.20 ± 20.02^ab	253.83 ± 30.36^ab	189.85 ± 61.02^a
HOMA-IR	4.96 ± 1.05^a	16.24 ± 5.65^b	10.75 ± 5.73^b	9.83 ± 4.51^b	9.84 ± 3.78^b	5.12 ± 0.70^a
HOMA-β	304.07 ± 53.72^c	9.68 ± 5.24^a	24.90 ± 14.54^a	13.62 ± 7.94^a	54.85 ± 27.51^ab	253.44 ± 30.98^c
AST (U/L)	88.00 ± 14.88	73.60 ± 7.63	91.20 ± 26.30	71.80 ± 6.64	88.66 ± 17.87	89.16 ± 15.49
ALT (U/L)	56.25 ± 12.55^a	77.75 ± 4.57^ab	81.80 ± 30.02^ab	88.25 ± 12.78^b	63.33 ± 18.18^a	57.33 ± 15.90^a
ALP (U/L)	188.80 ± 19.86^a	898.60 ± 174.49^bc	578.00 ± 163.45^b	510.50 ± 94.38^b	472.00 ± 74.99^b	214.42 ± 78.21^a
Urea (mg/dL)	48.00 ± 6.16^a	93.00 ± 16.40^ac	67.80 ± 12.69^ab	59.25 ± 22.93^a	42.00 ± 11.78^a	47.66 ± 9.00^a
Creatinine (μg/dL)	582.00 ± 70.49^a	485.00 ± 40.41^a	563.33 ± 51.63^a	550.00 ± 74.38^ab	675.00 ± 95.23^ab	471.42 ± 49.13^a

Data are presented as the mean ± SD of eight animals.

^a–c Values with different letters along a row are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw); HOMA-IR: Homeostatic Model Assessment – Insulin Resistance; HOMA-β: Homeostatic Model Assessment – Beta-cell function; AST; Aspartate transaminase; ALT: Alanine transaminase; ALP: Alkaline phosphatase.

Table 2. Liver weights and liver glycogen concentrations in different animal groups at the end of the experimental period.

	NC	DBC	DZL	DZH	DMF	NZT
Liver weight (g)	11.80 ± 2.35	10.98 ± 1.96	10.33 ± 1.96	10.28 ± 1.22	10.39 ± 1.73	11.94 ± 1.87
Relative liver weight (%)	3.28 ± 0.33^a	3.96 ± 0.15^b	4.01 ± 0.33^b	3.81 ± 0.14^ab	3.67 ± 0.12^a	3.39 ± 0.43^a
Liver glycogen (mg/g tissue)	3.53 ± 0.83^b	1.54 ± 0.13^a	2.20 ± 0.86^a	2.40 ± 0.54^ab	2.65 ± 0.38^ab	2.97 ± 1.02^ab

Data are presented as the mean ± SD of eight animals.

^a–b Values with different letters along a row are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).

Relative liver weight is the ratio of the liver weight of an animal to the total body weight of which was calculated using the following formula:.

Relative liver weight = (liver weight in gram/body weight in gram) × 100.

Table 3. Serum lipid profiles in different animal groups at the end of the experimental period.

	(mg/dL)
Serum lipids	NC	DBC	DZL	DZH	DMF	NZT
Total cholesterol	66.25 ± 6.39	76.25 ± 10.62	61.00 ± 9.45	79.25 ± 17.25	74.63 ± 12.10	80.66 ± 11.28
HDL cholesterol	31.00 ± 9.55^b	19.80 ± 1.64^a	28.50 ± 5.24^ab	26.00 ± 9.27^ab	28.14 ± 5.39^ab	32.42 ± 8.48^b
LDL cholesterol	19.85 ± 5.35	27.45 ± 4.34	18.60 ± 8.47	16.50 ± 6.90	25.98 ± 7.43	30.57 ± 8.48
Triglycerides	102.50 ± 27.49^a	184.75 ± 40.96^b	113.50 ± 30.12^a	198.40 ± 7.50^b	120.13 ± 27.42^a	92.00 ± 14.22^a

Data are presented as the mean ± SD of eight animals.

^a–b Values with different letters along a row are significantly different from each other (Tukey’s-HSD multiple range post hoc test, p < 0.05). NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw); HDL: high-density lipoproteins; LDL: low-density lipoproteins.

Figure 5. Representative sections of histopathological examinations of the pancreas from different animal groups. The NC group had higher number of cells per islet while the DBC and DZL group had smaller pancreatic islets with very few cells. The DZH had relatively higher number of cells per islet compared to DBC and DZL groups but far lower than the NC group. NC: Normal Control; DBC: Diabetic Control; DZL: Diabetic Ziziphus mucronata low dose (150 mg/kg bw); DZH: Diabetic Ziziphus mucronata high dose (300 mg/kg bw); DMF: Diabetic metformin; NZT: Normal Ziziphus mucronata toxicological dose (300 mg/kg bw).