Caffeic acid attenuates memory dysfunction and restores the altered activity of cholinergic, monoaminergic and purinergic in brain of cadmium chloride exposure rats.

Objectives This study aims to evaluate the neuroprotective effect of caffeic acid (CAF) against cadmium chloride (CdCl2) in rats via its effect on memory index as well as on altered enzymatic activity in the brain of CdCl2-induced neurotoxicity. Methods The experimental rats were divided into seven groups (n=6 rats per group) of healthy rats (group 1), CdCl2 -induced (CD) (3 mg/kg BW) rats (group 2), CD rats + Vitamin C (group 3), CD rats + CAF (10 and 20 mg/kg BW respectively) (group 4 & 5), and healthy rat + CAF (10 and 20 mg/kg BW respectively) (group 6 & 7). Thereafter, CdCl2 and CAF were administered orally to the experimental rats in group 2 to group 5 on daily basis for 14 days. Then, the Y-maze test was performed on the experimental rats to ascertain their memory index. Results CdCl2 administration significantly altered cognitive function, the activity of cholinesterase, monoamine oxidase, arginase, purinergic enzymes, nitric oxide (NOx), and antioxidant status of Cd rats (untreated) when compared with healthy rats. Thereafter, CD rats treated with vitamin C and CAF (10 and 20 mg/kg BW) respectively exhibited an improved cognitive function, and the observed altered activity of cholinesterase, monoamine oxidase, arginase, purinergic were restored when compared with untreated CD rats. Also, the level of brain NOx and antioxidant status were significantly (p<0.05) enhanced when compared with untreated CD rats. In the same vein, CAF administration offers neuro-protective effect in healthy rats vis-à-vis improved cognitive function, reduction in the activity of some enzymes linked to the progression of cognitive dysfunction, and improved antioxidant status when compared to healthy rats devoid of CAF. Conclusions This study demonstrated the neuroprotective effect of CAF against CdCl2 exposure and in healthy rats.

Effect of Bitter-leaf (Vernonia amygdalina) Flavored Non-alcoholic Wheat Beer (NAWB) on, Insulin and GLUT-2 expression in Pancreas of High fat diet/Streptozotocin (HFD/STZ) Induced Diabetic Wistar Rats.

Purpose: In the management of type 2 diabetes (T2D), dietary intervention has been proposed to be highly effective. This study, therefore, investigated the effect of bitter leaf-flavored non-alcoholic wheat beer (NAWB) on insulin secretion and GLUT-2 expression in the pancreas of STZ-induced diabetic rats. Methods: In this study, the rats received a single intraperitoneal injection (i.p.) of STZ (35 mg/kg) after being fed a high-fat diet for 14 days to induce T2D. The rats were treated with bitter leaf flavored NAWB samples (100%HP- Hops only, 100%BL-Bitter leaf only, 75,25BL- 75% Hops, 25% Bitter Leaf, 50:50BL- 50% Hops:50% Bitter Leaf, and 25:75BL-25%Hops:75% Bitter Leaf) and Acarbose for 14 days. The superoxide dismutase, catalase, and glutathione peroxidase activity were also determined. Results: The results from this study showed a correlation between GLUT-2 and Insulin expression. There was an upregulation of Insulin as GLUT-2 expression was upregulated. Furthermore, the treated groups showed better antioxidant activity when compared with the diabetic control. Conclusion: Bitter leaf-flavored NAWB might thus be a good dietary intervention for type 2 diabetics.

Antioxidant-rich Terminalia catappa fruit exerts antihypertensive effect via modulation of angiotensin-1-converting enzyme activity and H2S/NO/cGMP signalling pathway in Wistar rats.

INTRODUCTION: The present study aimed at investigating the effect of Terminalia catappa fruits on blood pressure, NO/cGMP signalling pathway, angiotensin-1-converting enzyme and arginase activity, and oxidative stress biomarkers in L-NAME-induced hypertensive rats. MATERIALS AND METHODS: Forty-two Wistar rats were divided into seven groups. Hypertension was induced via oral administration of 40 mg/kg of L-NAME for 21 days. Thereafter, the hypertensive rats were treated with Terminalia catappa fruit-supplemented diet and sildenafil citrate for 21 days. The blood pressure was measured and cardiac homogenate was prepared for biochemical analyses. RESULTS: The results showed that L-NAME caused a significant (p < 0.05) increase in systolic and diastolic blood pressure, and heart rate as well as ACE, arginase and PDE-5 activity, with a simultaneous decrease in NO and H2S levels as well as increased oxidative stress biomarkers. However, treatment with Terminalia catappa fruits-supplemented diets and sildenafil citrate lowered blood pressure and modulated ACE, arginase, and PDE-5 activity, improved NO and H2S levels, as well as antioxidant status. CONCLUSION: Findings presented in this study provide useful information on the antihypertensive property of Terminalia catappa fruits, alongside some possible mechanisms. Hence, Terminalia catappa fruits could be considered a dietary regimen and functional food in alleviating hypertension.

Glycemic indices and effect of bitter leaf (Vernonia amygdalina) flavored non-alcoholic wheat beer (NAWB) on key carbohydrate metabolizing enzymes in high fat diet fed (HFD)/STZ-induced diabetic Wistar rats.

In a bid to make the use of functional food easier in the management and prevention of diseases, product development and fortification from/with functional foods have become the recent focus of research. This study, therefore, sought to exploit the recent trend in the brewing industry on the production of non-alcoholic beers by investigating the possibility of having a non-alcoholic beer flavored with bitter leaf, a known plant widely reported to have a strong hypoglycemic effect, as against the traditional use of hops, and the effect of the produced beer on the glycemic indices and various diabetic biochemical parameters that serve as biomarkers for type-2 diabetes (T2D). The glycemic indices, as well as the inhibitory potentials of bitter leaf-flavored Non-alcoholic wheat beer (NAWB) in ratios of 100%HP, 100%BL, 75:25BL, 50:50BL, and 25:75BL, on enzymes linked to a high-fat diet/streptozocin (HFD/STZ)-induced T2D albino Wistar rats were investigated. There were no significant difference (p > .05) between the starch (1.72-1.77 mg/100 mL), amylose (0.22-0.24 mg/100 mL), and amylopectin (1.49-1.53 mg/100 mL) contents of the various samples. The Glycemic Index (GI) of the samples ranged from 36 to 73 with 75:25Bl and 50:50BL have the lowest (36) values. The samples reduced blood glucose levels and inhibited pancreatic α-amylase, lipase, and intestinal α-glucosidase activity. The inhibitory potentials of these beer samples on α-amylase and α-glucosidase as well as their ability to reduce blood glucose levels in diabetic rats thus making the bitter leaf flavored NAWB a suitable healthy beverage for better glycemic control in diabetics. PRACTICAL APPLICATIONS: This study revealed the potential of producing non-alcoholic wheat beer flavored with bitter leaves as a possible substitute for hops. The potential inherent in bitter leaf in the management of type 2 diabetes can thus be made available through a far-reaching beverage medium such as non-alcoholic beer to help in the treatment/management of T2D. The results of this research could be an eye-opener to the possible utilization of bitter leaf and by extension other plants that have been reported in the management of T2D. The use of the bitter leaf as a substitute for hops in the production of non-alcoholic beer in the brewing industry could help in a health-oriented campaign for safe drinks that could be helpful in the control of blood glucose levels of diabetic patients.

Phytochemical composition and antioxidant properties of methanolic extracts of whole and dehulled Bambara groundnut (Vigna subterranea) seeds.

The distribution of phytochemicals and their contribution to antioxidant potentials in whole and dehulled Bambara groundnut (BGN) seeds was evaluated. Whole BGN seeds were sorted using the testa and hilium colour and further grouped into whole and dehulled BGN seeds. Extractions of both whole and dehulled BGN seeds was done using methanol and the extracts assayed for total phenolics (TPC), flavanol, flavonol, anthocyanin content, oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP). Methanolic extract of whole BGN seed exhibited higher flavanol and flavonol content as well as significantly higher in-vitro antioxidant activities than dehulled BGN seeds. The TPC of whole BGN seed extract ranged from 3.6 to 11.0 GAE/g, while that of dehulled BGN ranged from 2.7 to 3.2 GAE/g. Identification of phenolics in whole and dehulled BGN seed extract using UPLC-qTOF-MS, revealed the presence of monoterpenoids (iridoids), phenolic acids, flavonoids and lignans. Bivariate correlations showed anthocyanin demonstrated weak positive correlation between flavanol, flavonol and ORAC for whole BGN seed extract; and negative correlation between flavanol, TPC, FRAP and ORAC for dehulled BGN. Aside the effect of dehulling, whole BGN seeds exhibited the presence of phytochemicals with beneficial properties for food and industrial application.

Effect of cooking on glycemic index, antioxidant activities, α-amylase, and α-glucosidase inhibitory properties of two rice varieties.

This study was designed to investigate the influence of cooking on the glycemic index (GI), amylose, and amylopectin contents of two rice varieties. Two rice varieties (foreign long rice and ofada) were sourced for, divided into two, one portion cooked and the other used raw. The sugar, starch, amylose, and amylopectin contents as well as glycemic indices, antioxidant properties, and the ability of the rice to inhibit carbohydrate-hydrolyzing enzymes (α-amylase and α-glucosidase) were determined. In addition, polyphenol content was determined. The results revealed that cooking caused a significant increase in starch content of the rice varieties. In the same vein, cooking increases the amylopectin content but has no effect on the amylose content. In addition, cooking shows no effect on polyphenol content but significantly increases radical scavenging ability of rice varieties used in this study. Furthermore, cooking lower the α-amylase and α-glucosidase inhibitory properties of two rice varieties except for foreign rice. However, the inhibitory effect of both cooked and raw foreign and ofada rice on α-amylase and α-glucosidase coupled with their low GI may explain their important role in controlling blood glucose level.

Antioxidant and Antihyperglycemic Properties of Three Banana Cultivars (Musa spp.).

Background. This study sought to investigate the antioxidant and antihyperglycemic properties of Musa sapientum (Latundan banana) (MSL), Musa acuminata (Cavendish banana) (MAC), and Musa acuminate (Red Dacca) (MAR). Materials and Methods. The sugar, starch, amylose, and amylopectin contents and glycemic index (GI) of the three banana cultivars were determined. Furthermore, total phenol and vitamin C contents and α-amylase and α-glucosidase inhibitory effects of banana samples were also determined. Results. MAC and MAR had the highest starch, amylose, and amylopectin contents and estimated glycemic index (eGI) with no significant different while MSL had the lowest. Furthermore, MAR (1.07 mg GAE/g) had a higher total phenol content than MAC (0.94 mg GAE/g) and MSL (0.96 mg GAE/g), while there was no significant difference in the vitamin C content. Furthermore, MAR had the highest α-amylase (IC50 = 3.95 mg/mL) inhibitory activity while MAC had the least (IC50 = 4.27 mg/mL). Moreover, MAC and MAR inhibited glucosidase activity better than MSL (IC50 3.47 mg/mL). Conclusion. The low sugar, GI, amylose, and amylopectin contents of the three banana cultivars as well as their α-amylase and α-glucosidase inhibitory activities could be possible mechanisms and justification for their recommendation in the management of type-2 diabetes.

Phenolic Composition and Evaluation of Methanol and Aqueous Extracts of Bitter Gourd (Momordica charantia L) Leaves on Angiotensin-I-Converting Enzyme and Some Pro-oxidant-Induced Lipid Peroxidation In Vitro.

This study sought to assess the effects of bitter gourd leaf extracts (methanol and aqueous) on enzyme linked with hypertension (angiotensin-I-converting enzyme and some pro-oxidants (iron sulfate, sodium nitroprusside, and cisplatin]-induced lipid peroxidation in rat kidney homogenates. Chromatographic analysis of the extract was done using high-performance liquid chromatography-diode array detection. The results revealed that methanol extract (IC50 = 109.63 µg/mL) had significantly (P < .05) higher angiotensin-I converting enzyme inhibitory activity than aqueous extract (IC50 = 182.95 µg/mL). Similarly, methanol extract had significantly (P < .05) higher inhibitory effect on Fe2+- and cisplatin-induced lipid peroxidation than aqueous extract. However, there was no significant (P > .05) difference in the inhibition of sodium nitroprusside-induced lipid peroxidation of both extracts. High-performance liquid chromatography-diode array detection analysis revealed the presence of quercetin, caffeic, gallic, and chlorogenic acids in the leaf. Thus, inhibition of angiotensin-I converting enzyme activity and the antioxidant properties of the extracts could be linked to the presence of phenolic phytochemicals.

Interaction of some commercial teas with some carbohydrate metabolizing enzymes linked with type-2 diabetes: a dietary intervention in the prevention of type-2 diabetes.

This study is aimed at assessing the inhibitory effect of teas on key enzymes (α-amylase and α-glucosidase) linked with type-2 diabetes and their antioxidant properties. Four samples of three brands were used; infusions of green tea (GT), 2 brands of black tea (BT), and a formulated herbal preparation for diabetes (ADT) (white tea, Radix Puerariae, Radix ophiopogonis, hawthorn berry, Chinese yam, and fragrant Solomon seal rhizome) were prepared and subsequently analyzed for their total phenol, ascorbic acid contents, antioxidant properties (2,2-Azizobis (3-Ethylbenzo-Thiazoline~6-sulfonate) "ABTS" scavenging ability and ferric reducing antioxidant property), and inhibition of pancreatic-α-amylase and intestinal-α-glucosidase in vitro. The study revealed that GT had the highest total phenol content, ascorbic acid content, ABTS∗ scavenging ability, and ferric reducing ability. Furthermore, all the teas inhibited Fe(2+) and sodium nitroprusside induced lipid peroxidation in pancreas, with GT having the highest inhibitory effect. Conversely, there was no significant difference (P > 0.05) in the inhibitory effects of the teas on α-amylase and α-glucosidase. The antidiabetic property of the teas could be attributed to their inhibitory effect on carbohydrate hydrolyzing enzymes implicated in diabetes and their antioxidant activities.