Mesozeaxanthin protects the liver and reduces cardio-metabolic risk factors in an insulin resistant rodent model

Figures & data

Table 1. Composition of diets (g/kg diet) fed to rats.

	Control	HFD
Casein	200.0	200.0
Starch	579.5	150.0
Sucrose	50.0	149.5
Soybean oil	70.0	–
Beef tallow	–	400.0
Cellulose	50.0	50.0
Vitamin–mineral premix*	45.0	45.0
l-cysteine	3.0	3.0
Choline bitartrate	2.5	2.5

Notes: *The vitamin–mineral premix provides the following (per kg): all-trans-retinyl acetate, 1.8 mg; cholecalciferol, 0.025 mg; all-rac-a-tocopherol acetate, 12,5 mg; menadione (menadione sodium bisulfate), 1.1 mg; riboflavin, 4.4 mg; thiamine (thiamine mononitrate), 1.1 mg; vitamin B-6, 2.2 mg; niacin, 35 mg; Ca-pantothenate, 10 mg; vitamin B-12, 0.02 mg; folic acid, 0.55 mg; d-biotin, 0.1 mg. manganese (from manganese oxide), 40 mg; iron (from iron sulfate), 12.5 mg; zinc (from zinc oxide), 25 mg; copper (from copper sulfate), 3.5 mg; iodine (from potassium iodide), 0.3 mg; selenium (from sodium selenite), 0.15 mg; choline chloride, 175 mg.

Figure 1. Chromatography (HPLC) of mesozeaxanthin.

Table 2. Effect of MZ supplementation on the body weight, visceral fat and liver weight in rats fed HFD for 12 weeks.

	Groups
Item	Control	MZ	HFD	HFD + MZ
Initial BW (g)	233.86 ± 5.42	234.43 ± 3.62	232.29 ± 3.93	234.43 ± 5.74
Final BW (g)	286.29 ± 5.65^b (122%)	291.71 ± 6.48^b (124.4%)	340.86 ± 5.00^a (146.7%)	326.29 ± 8.25^a (139%)
Feed intake (g/d)	23.54 ± 0.49^a	23.31 ± 0.40^a	19.16 ± 0.44^b	19.28 ± 0.78^b
Visceral fat (g)	7.79 ± 0.25^c	7.69 ± 0.26^c	29.54 ± 2.20^a	15.33 ± 0.30^b
Liver (g)	12.29 ± 0.21^c (4.29%)	11.84 ± 0.28^c (4.05%)	20.56 ± 0.60^a (6.03%)	17.19 ± 0.79^b (5.26%)

Notes: MZ, mesozeaxanthin; HFD, high-fat diet; data are expressed as mean±SEM of 7 rats from each group. Superscripts a–c indicate that means in the same row without a common superscript differ significantly (P < 0.05).

Table 3. Effects of MZ on biochemical parameter levels in rats fed HFD for 12 weeks.

Item	Groups
	Control	MZ	HFD	HFD + MZ
Glucose (mmol/L)	4.38 ± 0.23^c	4.45 ± 0.24^c	10.83 ± 0.29^a	9.19 ± 0.11^b
Insulin (pmol/L)	306.34 ± 10.33^c	285.69 ± 12.05^c	1335.50 ± 30.98^a	829.52 ± 29.26^b
HOMA-IR	8.60 ± 0.35^c	8.14 ± 0.26^c	92.66 ± 4.52^a	48.83 ± 2.84^b
FFA (mM)	1.23 ± 0.09^c	1.02 ± 0.06^c	3.81 ± 0.23^a	2.03 ± 0.06^b
Leptin (ng/mL)	30.71 ± 2.88^c	29.57 ± 3.09^c	107.71 ± 3.93^a	75.43 ± 3.95^b
Adiponectin (mg/mL)	10.37 ± 0.28^a	11.02 ± 0.39^a	5.97 ± 0.07^c	8.63 ± 0.20^b
T-C (mmol/L)	1.32 ± 0.02^b	1.27 ± 0.02^b	2.15 ± 0.09^a	1.41 ± 0.03^b
HDL-C (mmol/L)	0.44 ± 0.01^bc	0.38 ± 0.02^c	0.54 ± 0.03^a	0.50 ± 0.01^ab
LDL-C (mmol/L)	0.69 ± 0.02^bc	0.63 ± 0.09^c	1.20 ± 0.08^a	0.86 ± 0.01^b
TG (mmol/L)	0.31 ± 0.01^c	0.27 ± 0.03^c	0.57 ± 0.03^a	0.41 ± 0.02^b
AST (U/L)	138.43 ± 7.80	135.00 ± 6.66	143.29 ± 6.61	134.14 ± 3.00
ALT (U/L)	72.71 ± 5.55	75.71 ± 4.99	77.29 ± 2.08	73.86 ± 3.83
ALP (U/L)	2012.00 ± 69.25	1989.86 ± 83.34	1983.86 ± 105.63	2060.14 ± 80.91
Albumin (g/L)	30.35 ± 0.50	29.63 ± 1.07	30.91 ± 0.83	29.96 ± 0.78
Total protein (g/L)	59.74 ± 1.25	60.49 ± 0.81	60.55 ± 1.15	61.00 ± 0.98
Bilirubin (µmol/L)	3.08 ± 0.17	3.93 ± 0.34	3.25 ± 0.19	3.76 ± 0.21
GGT (U/L)	9.98 ± 0.01	9.97 ± 0.03	9.98 ± 0.04	9.97 ± 0.02
BUN (mmol/L)	3.55 ± 0.19	3.47 ± 0.44	3.72 ± 0.35	3.23 ± 0.20
CRE (µmol/L)	7.07 ± 0.18	6.63 ± 0.11	7.43 ± 0.23	6.36 ± 0.27

Notes: MZ, mesozeaxanthin; HFD, high-fat diet; FFA, free fatty acids; T-C, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; TG, triglycerides; AST, aspartate aminotransferase; ALT, alanine transferase; ALP, alkaline phosphatase; GGT, gamma-glutamyltransferase; BUN, blood urea nitrogen; CRE, creatinine. Data are expressed as mean±SEM of 7 rats from each group. Superscripts a–c indicate that means in the same row without a common superscript differ significantly (P < 0.05).

Table 4. Effects of MZ on the antioxidant status rats fed HFD for 12 weeks.

Item	Groups
	Control	MZ	HFD	HFD + MZ
Serum MDA (nmol/mL)	0.87 ± 0.03^c	0.73 ± 0.03^c	1.88 ± 0.07^a	1.56 ± 0.06^b
Liver MDA (nmol/mg protein)	1.82 ± 0.06^c	1.63 ± 0.09^c	3.82 ± 0.06^a	2.84 ± 0.12^b
Serum TAC (nmol Trolox Equiv. per mg protein)	1.18 ± 0.09^a	1.28 ± 0.11^a	0.46 ± 0.05^b	0.74 ± 0.04^b
Liver SOD (U/mg protein)	182.86 ± 4.61^a	196.57 ± 4.42^a	106.29 ± 2.50^c	134.43 ± 2.52^b
Liver CAT (U/mg protein)	299.71 ± 8.45^ab	313.57 ± 9.80^a	253.43 ± 9.42^c	276.43 ± 9.66^bc
Liver GSHPx (U/mg protein)	41.29 ± 0.94^b	53.14 ± 2.40^a	16.86 ± 1.16^d	26.71 ± 3.54^c
Zeaxanthin + meso-zeaxanthin (mg/g)	-	6.36 ± 0.54^a	-	4.52 ± 0.64 ^b
Lutein (mg/g)	-	8.23 ± 1.45^a	-	5.88 ± 1.04 ^b

Notes: MZ, mesozeaxanthin; HFD, high-fat diet; MDA, malondialdehyde; TAC, total antioxidant capacity; SOD, superoxide dismutase; CAT, catalase; GSHPx, glutathione peroxidase. Data are expressed as mean±SE of 7 rats from each group. Superscripts a–c indicate that means in the same row without a common superscript differ significantly (P < 0.05).

Figure 2. Hepatic NF-κB, TNF-α, BCO2, IRS-1,PPAR-γ Nrf-2 and HO-1 expression levels in mesozeaxanthin (MZ) supplemented high-fat diet (HFD) fed rats and control groups.

Notes: The Western blot strips of the proteins measured in this study are shown in Panel A. Panels B–F show the expression level of NF-κB, TNF-α, BCO2, IRS-1, PPAR-γ, Nrf-2 and HO-1 in various groups. The intensity of the bands shown in Panel A was quantified by densitometric analysis. Data are expressed as a ratio of normal control value (set to 100%). Each bar represents the mean and standard error of mean. Blots were repeated at least three times (n = 3) and only a representative blot is shown in Panel A. β-Actin was included to ensure equal protein loading.