Hibiscus sabdariffa calyx palliates insulin resistance, hyperglycemia, dyslipidemia and oxidative rout in fructose-induced metabolic syndrome rats.

BACKGROUND: The effect of Hibiscus sabdariffa calyx extract was evaluated in high-fructose-induced metabolic syndrome rats. Insulin resistance, hyperglycemia, dyslipidemia and oxidative rout were induced in rats using high-fructose diet. High-fructose diet-fed rats were administered 100 and 200 mg kg(-1) body weight of H. sabdariffa extract for 3 weeks, starting from week 7 of high-fructose diet treatment. RESULTS: High-fructose diet significantly (P < 0.05) increased the serum levels of blood glucose, insulin, total cholesterol (TC), triacylglycerol (TAG), low-density lipoprotein cholesterol (LDLc) and very-low-density lipoprotein cholesterol (VLDLc), with a concomitant reduction in high-density lipoprotein cholesterol (HDLc). These alterations were significantly ameliorated by the extract. High-fructose diet-mediated decreases in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-red) and glucose 6-phosphate dehydrogenase (Glc 6-PD) were significantly (P < 0.05) attenuated. Altered levels of reduced glutathione (GSH) and glutathione disulfide (GSSG) were significantly (P < 0.05) restored to normal. High-fructose diet-mediated increases in the concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl and percentage fragmented DNA were significantly (P < 0.05) lowered by the Hibiscus extract. CONCLUSION: Overall, aqueous extract of H. sabdariffa palliates insulin resistance, hyperglycemia, dyslipidemia and oxidative rout in high-fructose-induced metabolic syndrome rats.

A fermented sorghum/millet-based beverage, Obiolor, extenuates high-fat diet-induced dyslipidaemia and redox imbalance in the livers of rats.

BACKGROUND: Obiolor, a non-alcoholic beverage produced from fermented sorghum and millet malts, is widely consumed on a daily basis by the Igala tribe in Nigeria and is closely associated with good health. The effect of Obiolor on dyslipidaemia, protein oxidation, lipid peroxidation and DNA fragmentation in the liver of rats fed a high-fat diet was investigated. RESULTS: High-fat diet-mediated alterations in liver and serum total cholesterol, triacylglycerol, high-density lipoprotein cholesterol, low-density cholesterol and very low-density lipoprotein cholesterol were significantly (P < 0.05) reversed by Obiolor. The beverage increased the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase in the liver of rats. These increases significantly (P < 0.05) attenuated the high-fat diet-mediated decrease in antioxidant enzymes. High-fat diet-mediated elevations in the levels of conjugated dienes, lipid hydroperoxides, malondialdehyde, protein carbonyl and DNA fragmentation in the livers of rats were lowered by the beverage. CONCLUSION: This study showed that Obiolor extenuated high-fat diet-mediated dyslipidaemia, protein oxidation, lipid peroxidation and DNA fragmentation in rats.

Nutritional and antioxidant dispositions of sorghum/millet-based beverages indigenous to Nigeria.

Sorghum/millet-based beverages, Obiolor and Pito, were evaluated for their nutritional and antioxidant dispositions. Analyzed Obiolor and Pito contained 96% and 97% moisture; 7.8% and 3.7% crude protein; 8.9% and 5.6% available carbohydrate; 0.39% and 0.31% crude fat; 0.3% and 0.2% crude fiber; 2.4% and 1.5% ash; and 459.3 and 164 kJ/g energy value, respectively. Obiolor and Pito (1.0 mL) scavenged 2,2-diphenyl-1-picrylhydrazyl by 87% and 81%; superoxide ion by 65% and 59%; hydrogen peroxide by 79% and 76%; and hydroxyl radical by 82% and 85%, respectively. The beverages significantly reduced ferric ion. Aflatoxin B1-mediated increase in lipid peroxidation products (conjugated dienes, lipid hydroperoxides, and malondialdehydes) and protein carbonyl in the microsomes were significantly (P < 0.05) reduced by the beverages. The data obtained from this study show that the sorghum-based beverages (Obiolor and Pito) can serve as functional foods, as evident from their antioxidant capabilities in addition to their gross energy content.

Phenolic extract of Parkia biglobosa fruit pulp stalls aflatoxin B1 – mediated oxidative rout in the liver of male rats

The effect of phenolic extract of Parkia biglobosa (Jacq.) R. Br. ex G. Don, Fabaceae, pulp on aflatoxin B1 induced oxidative imbalance in rat liver was evaluated. Thirty-five male rats were randomized into seven groups of five animals each. Rats in group A served as control and received vehicle for drug administration (0.5% DMSO) once daily at 24 h intervals for six weeks. Rats in groups B, D, E, F and G, received aflatoxin B1 (167 μg/kg body weight) in 0.5% DMSO for three weeks, starting from the third week of the experimental period. Rats in Group C received 400 mg/kg bodyweight of the extract for six weeks, while groups D, E and F rats were treated with 100, 200 and 400 mg/kg bodyweight of the extract for six weeks respectively. Group G rats received 100 mg/kg body weight of vitamin C. Aflatoxin B1-mediated decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase were significantly attenuated. Aflatoxin B1 mediated the elevation in malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and significantly lowered DNA fragmentation percentage. Overall, the phenolic extract of P. biglobosa pulp stalls aflatoxin B1-mediated oxidative rout by enhancing antioxidant enzyme activities leading to decreased lipid peroxidation, protein oxidation and DNA fragmentation.

Phenolic extract of Dialium guineense pulp enhances reactive oxygen species detoxification in aflatoxin B1 hepatocarcinogenesis.

This study investigated the effect of Dialium guineense pulp phenolic extract on aflatoxin B1 (AFB1)-induced oxidative imbalance in rat liver. Reactive oxygen species (ROS) scavenging potentials of free and bound phenolic extract of D. guineense (0.2-1.0 mg/mL) were investigated in vitro using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide ion (O2(-)), hydrogen peroxide (H2O2), hydroxyl radical, and ferric ion reducing system. In the in vivo study, 35 animals were randomized into seven groups of five rats each. Free and bound phenolic extract (1 mg/mL) produced 66.42% and 93.08%, 57.1% and 86.0%, 62.0% and 90.05%, and 60.11% and 72.37% scavenging effect on DPPH radical, O2(-) radical, H2O2, and hydroxyl radical, while ferric ion was significantly reduced. An AFB1-mediated decrease in the activities of ROS detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glucose 6 phosphate dehydrogenase) was significantly attenuated (P<.05). AFB1-mediated elevation in the concentrations of oxidative stress biomarkers; malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and percentage DNA fragmentation were significantly lowered by D. guineense phenolic extract (P<.05). Overall, the in vitro and in vivo effects suggest that D. guineense phenolic extract elicited ROS scavenging and detoxification potentials, as well as the capability of preventing lipid peroxidation, protein oxidation, and DNA fragmentation.