Protective effect of Momordica charantia water extract against liver injury in restraint-stressed mice and the underlying mechanism

Figures & data

Table 1. Main chemical compounds of Momordica charantia water extract.

	Compounds	Content
Polysaccharide (g/100 g)		27.92 ± 0.58
Protein (g/100 g)		15.80 ± 0.18
Saponin composition (μg/g)	Momordicoside A	4.82 ± 0.09
	Momorcharaside A	5.11 ± 0.06
	Kuguacin N	0.34 ± 0.03
	Momordicoside F2	58.62 ± 0.64
	Momordicoside K	101.24 ± 0.82
	Karaviloside XI	0.22 ± 0.03
	(23E)-3β,7β,25-trihydroxycucubita-5,23-dien-19-al	23.15 ± 0.42
Phenolic composition (mg/100 g)	Vanillic acid	39.18 ± 2.50
	Epicatechin	388.63 ± 9.30
	Rutin	27.88 ± 3.18

Values are the means ± SD (n = 3).

Figure 1. Representative photomicrographs of liver sections from each group of mice stained with hematoxylin and eosin (H&E) (observation under an optical microscope (200×)). (A) NC group: the structure of the liver cells was intact, and the structure of the hepatic cords was clear. (B) Model group: the volume of the liver cells decreased; some individual cells were pyknotic and spottily necrotic. (C) VC group: the structure of the liver cells was basically intact. (D) MWEL group: the structure of the liver cells was relatively intact; the volumes of a small number of liver cells decreased, and some individual liver cells were necrotic. (E) MWEM group: the structure of the liver cells was relatively intact; no significant injury occurred to the liver cells. (F) MWEH group: the structure of the liver cells was intact and in an orderly arrangement, similar to that of the liver cells in the NC group. NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw; MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.

Figure 2. Effect of Momordica charantia water extract on the serum ALT and AST activities in the restraint-stressed mice. Values are expressed as the mean ± SD (n = 10). Different letters for the same index represent significant differences at p < .05. NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw; MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.

Table 2. Effect of Momordica charantia water extract on the redox status in the liver and serum of restraint-stressed mice.

Groups	Liver				Serum
	GSH (mg/g prot)	GSH-PX (U^#/mg prot)	TBARS (nmol MDA equivalents/mg prot)	ORAC (U^﹡/mL)	TBARS (nmol MDA equivalents/mL)	ORAC (U^﹡/mL)
NC	1.85 ± 0.26^ab	845.98 ± 54.89^a	8.60 ± 0.17^cd	45,251.28 ± 482.79^a	21.90 ± 0.83^b	212,727.87 ± 32,807.35^a
Model	1.31 ± 0.24^c	512.54 ± 71.53^b	17.97 ± 1.77^a	35,139.14 ± 7826.71^b	27.41 ± 4.25^a	137,634.14 ± 4885.29^b
VC	2.28 ± 0.27^a	828.77 ± 153.04^a	9.93 ± 2.59^cd	44,234.03 ± 3609.27^a	18.94 ± 2.37^bc	204,685.80 ± 13,517.46^a
MWEL	1.47 ± 0.25^bc	563.44 ± 132.25^b	13.54 ± 1.14^b	52,899.01 ± 6054.38^a	20.27 ± 3.14^bc	202,293.78 ± 39,726.58^a
MWEM	1.97 ± 0.30^a	535.65 ± 98.59^b	8.02 ± 0.97^d	48,718.48 ± 5602.71^a	15.84 ± 2.01^c	208,096.94 ± 44,471.94^a
MWEH	1.84 ± 0.50^ab	541.01 ± 88.76^b	11.15 ± 2.39^bc	45,619.79 ± 8724.11^a	18.36 ± 1.57^bc	200,251.61 ± 21,154.44^a

U^# = One milligram protein decreases 1 μmol/L GSH concentration in the system every minute when the non-enzymatic reaction effect is deducted. U^﹡ = the corresponding integral area of 1 μmol/L Trolox on the fluorescence quenching curve. Values are expressed as the mean ± SD (n = 10).

The values within each column marked by different letters are significantly different (p < .05).

Abbreviations: NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw. MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.

Table 3. Effect of Momordica charantia water extract on inflammatory cytokines in the livers of restraint-stressed mice.

Groups	NO (μmol/g prot)	iNOS (U^#/mg prot)
NC	0.25 ± 0.10^d	1.92 ± 0.16^c
Model	0.76 ± 0.17^a	4.20 ± 0.58^a
VC	0.42 ± 0.09^bc	3.03 ± 0.82^b
MWEL	0.32 ± 0.08^cd	1.69 ± 0.37^c
MWEM	0.51 ± 0.04^bc	1.39 ± 0.23^c
MWEH	0.53 ± 0.05^b	1.72 ± 0.56^c

U^# = every mg of tissue protein that produces 1 nmol of NO every minute. Values are expressed as the mean ± SD (n = 10).

The values within each column marked by different letters are significantly different (p < .05).

Abbreviations: NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw.MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.

Figure 3. Effect of Momordica charantia water extract on iNOS expression in the livers of restraint-stressed mice. NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw; MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.

Table 4. Effect of Momordica charantia water extract on ROS, MMP (JC-1 ration) and the mitochondrial respiratory chain complex I and II activities in the livers of restraint-stressed mice.

Groups	ROS (relative fluorescence intensity)	Membrane potential(aggregate/monomer)	Complex I(μmol/mg prot)			Complex II(μmol/mg prot)
			1 min	2 min	3 min	1 min	3 min	5 min
NC	1974.75 ± 477.50^cd	0.98 ± 0.01^a	9.60 ± 1.02^a	24.29 ± 2.78^a	43.34 ± 7.20^a	41.09 ± 7.34^a	47.26 ± 8.78^a	49.27 ± 5.04^a
Model	4888.83 ± 448.27^a	0.71 ± 0.08^c	4.41 ± 0.48^d	15.25 ± 4.35^c	22.95 ± 2.95^b	10.38 ± 6.23^c	13.52 ± 7.52^c	17.07 ± 6.91^d
VC	1555.17 ± 206.05^d	0.82 ± 0.10^b	7.93 ± 1.67^b	21.12 ± 2.72^ab	36.45 ± 1.51^a	19.96 ± 3.31^b	23.09 ± 4.99^b	27.98 ± 4.20^c
MWEL	2883.17 ± 431.78^bc	0.82 ± 0.09^b	6.25 ± 0.15^c	18.39 ± 1.08^bc	28.89 ± 5.82^b	27.32 ± 8.92^b	30.61 ± 9.32^b	38.12 ± 8.51^b
MWEM	2963.83 ± 692.56^bc	0.83 ± 0.05^b	7.66 ± 0.47^c	20.82 ± 0.24^ab	37.90 ± 2.31^a	22.85 ± 6.41^b	26.41 ± 4.43^b	32.57 ± 5.39^bc
MWEH	3452.51 ± 956.17^b	0.84 ± 0.05^b	8.72 ± 0.17^ab	21.72 ± 1.71^ab	37.17 ± 1.45^a	25.42 ± 6.08^b	30.81 ± 7.83^b	34.16 ± 8.61^bc

Values are expressed as the mean ± SD (n = 8). The values within each column marked by different letters are significantly different (p < .05).

Abbreviations: NC, normal control; Model, restraint stress model; VC, restraint-stressed mice treated with vitamin C 250 mg/kg bw; MWEL, restraint-stressed mice treated with M. charantia water extract 250 mg/kg bw; MWEM, restraint-stressed mice treated with M. charantia water extract 500 mg/kg bw; MWEH, restraint-stressed mice treated with M. charantia water extract 750 mg/kg bw.