ANTIOXIDANT AND INHIBITORY EFFECT OF SELECTED GHANAIAN VEGETABLES ON NITRIC OXIDE EXPRESSION IN LIPOPOLYSACCHARIDE-INDUCED MACROPHAGE CELLS

Objective: Nitric oxide (NO) is a signaling molecule that plays a key role in the pathogenesis of inflammation. Inhibitors of NO may be useful candidates for the treatment of inflammatory diseases. The study aimed to determine the antioxidant and inhibitory effect of commonly used Ghanaian vegetables, namely Corchorus olitorius (CO), Solanum melongena (SM), Solanum torvum (ST), Xanthosoma sagittifolia (XS) and Abelmoschus esculentus (AE) on NO expression in a Lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cell line. Methods: The cytotoxic effects of the vegetables on the cell line were determined using a tetrazolium-based colorimetric assay. The inflammatory activity was determined by measuring the inhibition of NO production in LPS-induced RAW 264.7 macrophage cells. Total antioxidant activity, total phenolic, flavonoid, and reduced glutathione contents were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay, Folin-Ciocalteu, aluminium chloride, and O-Phthalaldehyde methods, respectively. Results: Our results showed that CO and ST significantly inhibited NO production in a concentration-dependent manner with good cell viability.  Solanum torvum also exhibited strong antioxidant activity (IC50= 0.466 ± 0.23 mg/mL) with total phenolic content of230.73 ± 1.84 mg/g GAE, while CO showed high flavonoid content (291.45 ± 2.14 mg/g QUE).  Abelmoschus esculentus recorded the highest glutathione content (58.6 µg/g GSH. Saponins, alkaloids, tannins, terpenoids, and cardiac glycosides were present in all the samples except SM and AE which lacked terpenoids. Conclusion: These findings suggest that CO and ST possess anti-inflammatory and antioxidant activities that could be explored as potential therapeutic remedies for inflammatory disorders

Determination of aflatoxin levels in bokina beverage

Objective: The main aim of this study was to investigate levels of total aflatoxin and aflatoxin M1 in bokina, a homemade non-alcoholic beverage prepared from dairy milk, millet and sugar.Methods: Bokina, dairy milk and millet were purchased monthly over a period of 7 months from bokina producers at Ashaiman and Nima, in Ghana. Total aflatoxin and aflatoxin M1 levels in these samples were measured using a fluorometric procedure and High-Performance Liquid Chromatography.Results: Aflatoxin levels in bokina samples ranged from 1.0 to 21.0 ppb for Ashaiman samples and 1.0 to 23.0 ppb for Nima samples. Out of 21 samples from each site 1 from Ashiaman and 2 from Nima had levels total aflatoxin above the acceptable limit of 20 ppb. Similarly, total aflatoxin levels millet samples ranged from 1.0 to 55.0 ppb for Ashaiman and 5.0 to 53.0 ppb for Nima samples, with 2 samples from Ashiaman and 6 from Nima having levels above 20ppb. The levels of Aflatoxin M1 in milk ranged from 0.09 to 6.20 ppb for Ashaiman samples and 0.13 to 12.55 ppb for Nima samples. Out of the samples, 12 from Ashiaman and 10 from Nima (n=21) had levels of Aflatoxin M1 above the acceptable limit of 0.5 ppb.Conclusion: Bokina samples tested were contaminated with aflatoxin. All doses of aflatoxin have a cumulative effect on the risk of cancer. Therefore, farmers and bokina producers must be educated on good storage practices and monitored to protect the public from aflatoxin exposure and toxicity

Effect of Cellgevity® Supplement on Selected Rat Liver Cytochrome P450 Enzyme Activity and Pharmacokinetic Parameters of Carbamazepine

Background. There is considerable evidence that many patients concurrently administer dietary supplements with conventional drugs, creating a risk for potential drug-supplement interaction. The aim of this study was to determine the effect of Cellgevity® supplement on selected rat liver cytochrome P450 (CYP) enzymes. Also, based on our previous finding, we sought to determine the effect of Cellgevity® on the pharmacokinetics of carbamazepine, a CYP3A4 substrate. Methods. Male Sprague–Dawley (SD) rats were randomly put into 5 groups and administered either distilled water (negative control), Cellgevity® (3 separate doses), or phenobarbital (positive control), per os. Modulation of liver CYP enzyme activity was evaluated after 30 days of treatment, using probe substrates, spectroscopic, and high-performance liquid chromatographic methods. In the pharmacokinetic study, 12 SD rats were put into 2 groups and administered carbamazepine plus normal saline (group 1) or carbamazepine plus Cellgevity® (group 2), per os, both over a period of 14 days. Blood samples from rats in the same group were collected after treatment. Serum samples were prepared and pooled together at each specific sampling time point. Levels of carbamazepine were determined using a fluorescence polarization immunoassay. Results. Activities of rat liver CYP1A1/2, CYP2C9, and CYP2D6 were significantly increased by Cellgevity® after 30-day treatment. Pharmacokinetic parameters for rats administered carbamazepine with Cellgevity® vis-a-vis carbamazepine with normal saline were as follows: Cmax; 20 μmol/L vs 11 μmol/L, AUC0⟶24; 347 μmol h/L vs 170 μmol h/L, Ke; 0.28 h−1 vs 0.41 h−1, and t1/2; 2.3 h vs 1.7 h, respectively. Conclusions. Cellgevity® increased the activity of rat CYP1A1/2, CYP2C9, and CYP2D6 enzymes and was found to alter the pharmacokinetics of carbamazepine in rats

In Vitro Antioxidant Potential and Effect of a Glutathione-Enhancer Dietary Supplement on Selected Rat Liver Cytochrome P450 Enzyme Activity

Background. There is considerable evidence that many people take dietary supplements including those of herbal origin as an alternative therapy to improve their health. One such supplement, with an amalgam of constituents, is CellGevity®. However, the effect of this dietary supplement on drug-metabolizing enzymes is poorly understood, as it has not been studied extensively. Therefore, we investigated the effect of CellGevity dietary supplement on selected rat liver microsomal cytochrome P450 (CYP) enzymes, the most common drug-metabolizing enzymes. We also determined the total antioxidant potential of this dietary supplement in vitro. Methods. To determine the antioxidant potential of CellGevity dietary supplement, 2,2-diphenyl-2-picryl-hydrazyl (DPPH), total phenolic, and flavonoid assays were used after initial preparation of a solution form of the supplement (low dose, LD; 4 mg/kg and high dose, HD; 8 mg/kg). Rats received oral administration of these doses of the supplement for 7 days, after which the effect of the supplement on selected liver CYP enzymes was assessed using probe substrates and spectroscopic and high-performance liquid chromatographic methods. Rats which received daily administration of 80 mg/kg of phenobarbitone and distilled water served as positive and negative controls, respectively. Results. The IC50 value of the supplement 0.34 ± 0.07 mg/ml compared to 0.076±0.03 mg/ml of the BHT (positive control). The total phenolic content of the supplement at a concentration of 2.5 mg/ml was 34.97 g gallic acid equivalent (GAE)/100 g while its total flavonoid content at a concentration of 2.5 mg/ml was 6 g quercetin equivalent (QE)/100 g. The supplement significantly inhibited rat CYP2B1/2B2 (LDT 92.4%; HDT 100%), CYP3A4 (LDT 81.2%; HDT 71.7%), and CYP2C9 (LDT 21.7%; HDT 28.5%) while it had no significant inhibitory effect on CYPs 1A1/1A2, CYP1A2, and CYP2D6. Conclusion. CellGevity dietary supplement possesses moderate antioxidant activity in vitro and has an inhibitory effect on selected rat liver CYP enzymes, suggesting its potential interaction with drugs metabolized by CYP enzymes