Blighia sapida leaves halt elevated blood glucose, dyslipidemia and oxidative stress in alloxan-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Blighia sapida leaves are used in the management of diabetes in Nigeria. Thus the antidiabetic activity of methanolic Blighia sapida leaf extract and its capability to halt oxidative stress and dyslipidemia in alloxan-induced diabetic rats were investigated. METHODS: In vitro antioxidant activity of the extract (0.2-1.0mg/mL) was investigated using 2,2-diphenyl-1-1picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, and hydroxyl radical and ferric ion reducing system. Antidiabetic was evaluated in alloxan-induced diabetic rats. RESULTS: The methanolic extract of Blighia sapida leaves at 1.0mg/mL scavenged DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical at 80.34%, 57.39%, 72.36% and 77.0% respectively, while ferric ion was significantly reduced. Single oral dose of the extract significantly reduced blood glucose level in a dose dependent manner with highest dose producing 18.6% reduction after 240min. Similar reduction was produced after 28 days of extract administration with the highest dose producing 65.65% reduction which compared significantly (P<0.05) with the control group and glibenclamide treated groups. Alloxan-induced diabetic mediated alterations in liver and serum cholesterol, triacylglycerides, high-density lipoprotein cholesterol (HDLc), low density lipoprotein (LDL) cholesterol and very low-density lipoprotein cholesterol (VLDLc) were significantly (P<0.05) restored by the extract. Methanolic extract of Blighia sapida leaves significantly attenuated the decrease in the activities of reactive oxygen species detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase) in the liver and pancreas of alloxan-induced diabetic rats. Elevation in the concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and fragmented DNA was significantly (P<0.05) lowered by Blighia sapida leaves extract. CONCLUSION: Overall, methanolic extract of Blighia sapida leaves at all doses used reduced blood glucose level and prevented oxidative stress and dyslipidemia in alloxan-induced diabetic rats.

Haematological parameters of alloxan-induced diabetic rats treated with leaf essential oil of Hoslundia opposita (Vahl).

The effect of leaf essential oil of Hoslundia opposita (Vahl) on the haematological parameters of alloxan-induced diabetic rats was investigated. Forty-eight albino rats (Rattus norvegicus), of average weight 132.5 g, were randomly selected into normal and diabetic groups, each with four sub-groups. The rats were treated with 110 and 220 mg/kg body weight (b. wt.) of the essential oil. 14.2 mg/kg body weight of metformin (Glucophage) was used as a reference drug. All treatments were administered, intraperitoneally, once a day for four days. Haematological parameters like haemoglobin (HGB), red blood cell (RBC) count, white blood cell (WBC) count, percentage lymphocytes (LYM) and neutrophils (NEU) were analysed. There were no significant differences (p > 0.05) in the erythrocyte indices of all the normal (non-diabetic) rats, both treated and untreated. However, there was a significant increase (p < 0.05) in the WBC count and a significant reduction (p < 0.05) in the lymphocyte (LYM) percentages of the normal (non-diabetic) rats administered with higher dose of the essential oil. The results also revealed a significant reduction (p < 0.05) and a significant increase (p < 0.05) in the RBC counts of untreated diabetic rats and diabetic rats administered 110 mg/kg b. wt. of the oil respectively. A significant increase (p < 0.05) in the LYM of diabetic untreated rats was also observed, while administration of metformin and 110 mg/kg b. wt. Hoslundia opposita leaf essential oil (HOLEO) to diabetic rats significantly (p < 0.05) reduced the LYM percentages to values within range of the normal control animals. Overall, administration of the oil has significant ameliorative effect on alloxan-induced anaemia in diabetic state and this may be of immense benefits in the management of type 2 diabetes and its associated haematological complications.

Performance and haematological indices in rats exposed to monocrotophos contamination.

Monocrotophos is an organophosphate pesticide used in agriculture to control insect pests. Changes in performance and haematological parameters (such as packed cell volume, white blood cells, neutrophils, eosinophils and lymphocytes) were used to assess the effect of the pesticide on rats chronically exposed to 12.5 parts per million (ppm), 25 ppm, 50 ppm, 100 ppm and 200 ppm for 10 days, while the control rats were placed on borehole water. Administration of the pesticide to the animals resulted in several physical deteriorations including appearance and agility. A significant reduction (p < .05) was observed in the weight gained by rats while the liver-to-body weight ratio increased significantly (p < .05) as the level of exposure to monocrotophos increased. Whereas packed cell volume, white blood cells and lymphocytes increased significantly (p < .05), neutrophils and eosinophils counts reduced significantly (p < .05) as the concentration of monocrotophos in the drinking water increased. Overall, the data indicated that exposure to monocrotophos portends serious consequences on the performance and haematological parameters of rats.

Effects of Aspergillus niger-fermented Terminalia catappa seed meal-based diet on selected enzymes of some tissues of broiler chicks.

Effects of Aspergillus niger-fermented Terminalia catappa seed meal-based diet on the activities of alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamate transferase (gamma-GT) in the crop, small intestine, gizzard, heart, liver and serum of broiler chicks were investigated. Milled T. catappa seed was inoculated with spores of A.niger (2.21 x 10(4) spores per ml) for 3 weeks. Forty-five day-old broiler chicks weighing between 27.62 and 36.21 g, were divided into three groups. The first group was fed soybean-based (control) diet; the second on raw T. catappa seed meal-based diet; and the third on A. niger-fermented T. catappa seed meal-based diet for 7 weeks. The results revealed a significantly increased (p<0.05) activity of ALP in the tissues. Contrarily, there were significant reductions (p<0.05) in the activities of ALP, ALT, AST and gamma-GT in the liver and heart of the broilers fed the raw T. catappa seed meal-based diet while there were significant increase (p<0.05) in the activities of these enzymes in the serum of the broilers in this group. The data obtained showed that A. niger-fermented T. catappa seed meal reduced the toxic effects of the raw seed meal on the tissues of broiler chicks.

Potassium bromate content of selected bread samples in Ilorin, Central Nigeria and its effect on some enzymes of rat liver and kidney.

Bread samples from five different locations (Gaa-Akanbi, Saw-Mill, Oloje, Fate-Basin and Zango) in Ilorin metropolis, Central Nigeria were analyzed for their potassium bromate content before they were employed as a source of carbohydrate in the formulation of diet for albino rats. A total of sixty (60) albino rats (Rattus norvegicus) were grouped into six (6) of ten (10) rats each. The rats in the first group served as control and they were placed on diet formulated with bromate-free bread. Animals in Groups 2-6 were placed on diet formulated with bread samples obtained from the five different locations in Ilorin metropolis. At the expiration of thirty (30) days feeding period, the animals were sacrificed and blood samples, liver and kidney tissues were collected for the assay of ALP, AST and ALT activities. The results showed a significant reduction (p<0.05) in the activities of these enzymes in the tissues when compared with the control. However, a significant increase (p<0.05) was observed in the activities of the selected serum enzymes. Overall, the data indicate adverse effects on the liver and kidney of rats fed on diet containing potassium bromate.

Effect of water contaminated with phthalate, benzene and cyclohexane on Clarias gariepinus' cellular system.

This study evaluates the effect of water contaminated with phthalate, benzene and cyclohexane (major components of municipal waste in Nigeria) on the cellular system of Clarias gariepinus. Standard enzyme assays were conducted for alkaline phosphatase, acid phosphatase, alanine transaminase, aspartate transaminase, lactate dehydrogenase, gamma glutamyl transpeptidase of selected tissues of C. gariepinus cultivated in contaminated water over a period of 56 days. Generally, a significant decrease in the activity of the enzymes of the tissues of C. gariepinus cultivated in contaminated water was observed relative to the control (p<0.05). Particularly, activity of alkaline phosphatase of liver of C. gariepinus cultivated in phthalate contaminated water was found to be 8.26+/-1.42 while that of control was 14.42+/-1.09. The activity of serum gamma glutamyl transpeptidase of serum of the same group of fish was found to be twice that of control. It could be inferred that membrane integrity of the tissues studied are compromised and that tissue dysfunction may result. Consumption of C. gariepinus cultivated in water contaminated with phthalate, benzene and cyclohexane could pose threats to public health.

Toxicological evaluation of the effect of water contaminated with lead, phenol and benzene on liver, kidney and colon of Albino rats.

The effect of water contaminated with phenol, benzene and lead on rats cellular system was investigated. Selected enzyme activity of the kidney and colon of rats was carried out. Standard enzyme assays were also conducted for selected liver enzymes such as alkaline and acid phosphatases, alanine and aspartate transaminases, and gamma glutamyl transpeptidase. Serum indices of liver and kidney function were also determined. The direct bilirubin of test rats were observed to be 3.2+/-0.2U/mol/l while that of control rat was 1.2+/-0.003 U/mol/l. The total bilirubin of test rats was found to be 8.4+/-0.8 U/mol/l while that of the control was 5.6+/-0.5 U/mol/l. Generally, enzymes activity in the tissues of test rats were found to be significantly (p<0.05) lower relative to control, while the enzyme activity of the serum of test rats was significantly (p<0.05) higher than control. It could be inferred that experimental data suggest possible damage to the tissues and that consumption of polluted water may account for increasing cases of renal and hepatic failure among people in developing countries.

Inhibition of Bacillus spores by combinations of heat, potassium sorbate, NaCl and pH.

Viability of spores of Bacillus cereus was totally inhibited at 85°C over 30 min by adding 0.4% (w/v) potassium sorbate with 6% (w/v) NaCl at pH 4.5. Viability of B. stearothermophilus spores was totally inhibited at 95°C for 45 min in a buffer at pH 4.2 containing 0.8% (w/v) potassium sorbate and 8% (w/v) NaCl. A synergistic inhibitory effect was demonstrated in some of the combinations. The inhibition may be due to interference with the heat-resistance apparatus of the spores.

Effect of chronic consumption of metabisulphite on the integrity of the rat kidney cellular system.

The effect of chronic consumption of metabisulphite, a food preservative, on the integrity of the rat kidney cellular system was investigated. The levels of activities of some 'marker' enzymes were measured both before and after administration of between 1 and 15 doses of the chemical compound. Feeding of metabisulphite (5 mg/kg body wt.) to rats resulted in loss of alkaline phosphatase activities from the kidney beginning after the first dose. This was accompanied by a reduction of lactate dehydrogenase activity which was noticed as a secondary reaction, taking place after five daily doses. This was accompanied by an increase in alkaline phosphatase and a decrease in lactate dehydrogenase activities in the serum. An increased urinary excretion of protein and alkaline phosphatase activity was also obtained. Other enzymes assayed (acid phosphatase and glutamate dehydrogenase activities) were not significantly affected in the tissues and urine. All these results indicated that there is cellular damage to rat kidney as a result of chronic consumption of metabisulphite. They also indicate that the damage was primarily on the plasma membrane. The proximity of the soluble portion of the cytoplasm to the plasma membrane also makes it a secondary site of injury in the kidney cell.

Effects of low-iron status and deficiency of essential fatty acids on some biochemical constituents of rat brain.

The effects of iron and essential fatty acids (EFA) on the development of the brain were studied in young rats. Male weanling rats were maintained on diets deficient in EFA, low in iron (9 ppm) or deficient in both EFA and iron. The low-iron status aggravated signs of EFA deficiency indicating decreases in both growth and brain weight. While the protein content of the brain was considerably reduced, the alkaline phosphatase (ALP) activity increased in all dietary regimes. The lipids and fatty acid components of the brain were affected both qualitatively and quantitatively by the diets. Myelin lipids and docosahexaenoic acid (DHA, 22:6) were reduced by the iron deficient diets and the effect was found to be greater in the deficiency of both EFA and iron. It appears that dietary iron has a significant role to play in the biosynthesis of prostaglandins and in the proper configurational development and functioning of the brain.

Effect of metabisulphite on sporulation and alkaline phosphatase in Bacillus subtilis and Bacillus cereus.

The effect of metabisulphite on spore formation and alkaline phosphatase activity/production in Bacillus subtilis and Bacillus cereus was investigated both in liquid and semi-solid substrates. While supplementary nutrient broth (SNB) and sporulation medium (SM) were used as the liquid growth media, two brands of powdered milk were used as the food (semi-solid) substrates. Under both aerobic and anaerobic conditions, B. subtilis was more resistant to metabisulphite than B. cereus while the level of enzyme production and spores formed were generally higher under aerobic than anaerobic conditions. The metabisulphite concentrations required to inhibit spore production as well as alkaline phosphatase synthesis/activity were found to be relatively low and well within safety levels for human consumption. It is concluded that metabisulphite is an effective anti-sporulation agent and a recommendation for its general use in semi-solid and liquid foods is proposed.

Effect of disulphite on protein and pyridine-2,6-dicarboxylic acid synthesis in sporulating cells of bacterial species.

The effect of disulphite on protein and pyridine-2,6-dicarboxylic acid (dipicolinic acid, DPA) synthesis was investigated in sporulating cells of Bacillus subtilis E52 and B. cereus W18. Progressive reductions were evident in the protein and DPA concentrations for both sporulating cells with increasing concentrations (100 to 600 micrograms ml-1) of disulphite. A significant (P less than 0.05) reduction in protein synthesis by disulphite was exhibited, culminating in a decrease in protein synthesis ranging from 50% to 1.4%, and 50% to 2.5%, in B. subtilis E52 and B. cereus W18, respectively. The same disulphite concentrations caused a significant (P less than 0.05) decrease in DPA synthesis ranging from 75% to 12.5% and 70% to 5%, for B. subtilis E52 and B. cereus W18, respectively. DPA synthesis was completely prevented at 500 and 600 micrograms ml-1 for B. subtilis E52 and B. cereus W18, respectively. A plausible mechanism for the inhibitory action of disulphite on sporulating cells of the bacteria is proposed.

Sporulation of bacterial species in the presence of metabisulphite.

The effect of metabisulphite on the sporulating ability of Bacillus subtilis E52 and B. cereus W18 was studied. Whereas metabisulphite concentrations of 500 and 600 micrograms ml-1 prevented sporulation of B. subtilis and B. cereus, respectively, lower concentrations caused reductions in their percentage sporulations. Glucose dehydrogenase (GDH) and alkaline phosphatase (ALP) activities of both sporulating bacteria were not detected at the stated metabisulphite concentrations. A relationship between the percentage sporulation of the bacteria and the activity of the enzymes in the presence of metabisulphite was exhibited. ALP activity may serve as an index of the effectiveness of the antisporulating activity of metabisulphite. Both enzymes are likely to be among the few targets for the antisporulating activity of metabisulphite.